Apache Tomcat

• Apache Tomcat 6.x vulnerabilities
• Fixed in Apache Tomcat 6.0.37
• Fixed in Apache Tomcat 6.0.36
• Fixed in Apache Tomcat 6.0.35
• Fixed in Apache Tomcat 6.0.33
• Fixed in Apache Tomcat 6.0.32
• Fixed in Apache Tomcat 6.0.30
• Fixed in Apache Tomcat 6.0.28
• Fixed in Apache Tomcat 6.0.24
• Fixed in Apache Tomcat 6.0.20
• Fixed in Apache Tomcat 6.0.18
• Fixed in Apache Tomcat 6.0.16
• Fixed in Apache Tomcat 6.0.14
• Fixed in Apache Tomcat 6.0.11
• Fixed in Apache Tomcat 6.0.10
• Fixed in Apache Tomcat 6.0.9
• Fixed in Apache Tomcat 6.0.6
• Not a vulnerability in Tomcat

This page lists all security vulnerabilities fixed in released versions of Apache Tomcat 6.x. Each vulnerability is given a security impact rating by the Apache Tomcat security team — please note that this rating may vary from platform to platform. We also list the versions of Apache Tomcat the flaw is known to affect, and where a flaw has not been verified list the version with a question mark.

Note: Vulnerabilities that are not Tomcat vulnerabilities but have either been incorrectly reported against Tomcat or where Tomcat provides a workaround are listed at the end of this page.

Please note that binary patches are never provided. If you need to apply a source code patch, use the building instructions for the Apache Tomcat version that you are using. For Tomcat 6.0 those are building.html and BUILDING.txt. Both files can be found in the webapps/docs subdirectory of a binary distributive.

If you need help on building or configuring Tomcat or other help on following the instructions to mitigate the known vulnerabilities listed here, please send your questions to the public Tomcat Users mailing list

If you have encountered an unlisted security vulnerability or other unexpected behaviour that has security impact, or if the descriptions here are incomplete, please report them privately to the Tomcat Security Team. Thank you.

Important: Session fixation CVE-2013-2067

FORM authentication associates the most recent request requiring authentication with the current session. By repeatedly sending a request for an authenticated resource while the victim is completing the login form, an attacker could inject a request that would be executed using the victim's credentials.

Note that the option to change session ID on authentication was added in Tomcat 6.0.21. In earlier 6.0.x releases, prevention of session fixation was an application responsibility. This vulnerability represents a bug in Tomcat's session fixation protection that was added in 6.0.21. Hence, only versions 6.0.21 onwards are listed as vulnerable.

This was fixed in revision 1417891.

This issue was identified by the Tomcat security team on 15 Oct 2012 and made public on 10 May 2013.

Affects: 6.0.21-6.0.36

Important: Denial of service CVE-2012-3544

When processing a request submitted using the chunked transfer encoding, Tomcat ignored but did not limit any extensions that were included. This allows a client to perform a limited DOS by streaming an unlimited amount of data to the server.

This was fixed in revision 1476592.

This issue was reported to the Tomcat security team on 10 November 2011 and made public on 10 May 2013.

Affects: 6.0.0-6.0.36

Important: Denial of service CVE-2012-2733

The checks that limited the permitted size of request headers were implemented too late in the request parsing process for the HTTP NIO connector. This enabled a malicious user to trigger an OutOfMemoryError by sending a single request with very large headers.

This was fixed in revision 1356208.

This was reported by Josh Spiewak to the Tomcat security team on 4 June 2012 and made public on 5 November 2012.

Affects: 6.0.0-6.0.35

Moderate: DIGEST authentication weakness CVE-2012-3439

Three weaknesses in Tomcat's implementation of DIGEST authentication were identified and resolved:

1. Tomcat tracked client rather than server nonces and nonce count.
2. When a session ID was present, authentication was bypassed.
3. The user name and password were not checked before when indicating that a nonce was stale.

These issues reduced the security of DIGEST authentication making replay attacks possible in some circumstances.

This was fixed in revision 1380829.

The first issue was reported by Tilmann Kuhn to the Tomcat security team on 19 July 2012. The second and third issues were discovered by the Tomcat security team during the resulting code review. All three issues were made public on 5 November 2012.

Affects: 6.0.0-6.0.35

Important: Bypass of security constraints CVE-2012-3546

When using FORM authentication it was possible to bypass the security constraint checks in the FORM authenticator by appending /j_security_check to the end of the URL if some other component (such as the Single-Sign-On valve) had called request.setUserPrincipal() before the call to FormAuthenticator#authenticate().

This was fixed in revision 1381035.

This issue was identified by the Tomcat security team on 13 July 2012 and made public on 4 December 2012.

Affects: 6.0.0-6.0.35

Important: Bypass of CSRF prevention filter CVE-2012-4431

The CSRF prevention filter could be bypassed if a request was made to a protected resource without a session identifier present in the request.

This was fixed in revision 1394456.

This issue was identified by the Tomcat security team on 8 September 2012 and made public on 4 December 2012.

Affects: 6.0.30-6.0.35

Important: Denial of service CVE-2012-4534

When using the NIO connector with sendfile and HTTPS enabled, if a client breaks the connection while reading the response an infinite loop is entered leading to a denial of service. This was originally reported as bug 52858.

This was fixed in revision 1372035.

The security implications of this bug were reported to the Tomcat security team by Arun Neelicattu of the Red Hat Security Response Team on 3 October 2012 and made public on 4 December 2012.

Affects: 6.0.0-6.0.35

Note: The issues below were fixed in Apache Tomcat 6.0.34 but the release vote for the 6.0.34 release candidate did not pass. Therefore, although users must download 6.0.35 to obtain a version that includes a fix for this issue, version 6.0.34 is not included in the list of affected versions.

Important: Information disclosure CVE-2011-3375

For performance reasons, information parsed from a request is often cached in two places: the internal request object and the internal processor object. These objects are not recycled at exactly the same time. When certain errors occur that needed to be added to the access log, the access logging process triggers the re-population of the request object after it has been recycled. However, the request object was not recycled before being used for the next request. That lead to information leakage (e.g. remote IP address, HTTP headers) from the previous request to the next request. The issue was resolved be ensuring that the request and response objects were recycled after being re-populated to generate the necessary access log entries.

This was fixed in revision 1185998.

This was identified by the Tomcat security team on 22 September 2011 and made public on 17 January 2012.

Affects: 6.0.30-6.0.33

Important: Authentication bypass and information disclosure CVE-2011-3190

Apache Tomcat supports the AJP protocol which is used with reverse proxies to pass requests and associated data about the request from the reverse proxy to Tomcat. The AJP protocol is designed so that when a request includes a request body, an unsolicited AJP message is sent to Tomcat that includes the first part (or possibly all) of the request body. In certain circumstances, Tomcat did not process this message as a request body but as a new request. This permitted an attacker to have full control over the AJP message permitting authentication bypass and information disclosure. This vulnerability only occurs when all of the following are true:

• The org.apache.jk.server.JkCoyoteHandler AJP connector is not used
• POST requests are accepted
• The request body is not processed

This was fixed in revision 1162959.

This was reported publicly on 20th August 2011.

Affects: 6.0.0-6.0.33

Mitigation options:

• Upgrade to Tomcat 6.0.35.
• Apply the appropriate patch.
• Configure both Tomcat and the reverse proxy to use a shared secret.
  (It is "request.secret" attribute in AJP <Connector>, "worker.workername.secret" directive for mod_jk. The mod_proxy_ajp module currently does not support shared secrets).
• Use the org.apache.jk.server.JkCoyoteHandler (BIO) AJP connector implementation.
  (It is automatically selected if you do not have Tomcat-Native library installed. It can be also selected explicitly: <Connector protocol="org.apache.jk.server.JkCoyoteHandler">).

References:

• AJP Connector documentation (Tomcat 6.0)
• workers.properties configuration (mod_jk)

Important: Denial of service CVE-2012-0022

Analysis of the recent hash collision vulnerability identified unrelated inefficiencies with Apache Tomcat's handling of large numbers of parameters and parameter values. These inefficiencies could allow an attacker, via a specially crafted request, to cause large amounts of CPU to be used which in turn could create a denial of service. The issue was addressed by modifying the Tomcat parameter handling code to efficiently process large numbers of parameters and parameter values.

This was fixed in revisions 1200601, 1206324 and 1229027.

This was identified by the Tomcat security team on 21 October 2011 and made public on 17 January 2012.

Affects: 6.0.0-6.0.33

Moderate: Multiple weaknesses in HTTP DIGEST authentication CVE-2011-1184

Note: Mitre elected to break this issue down into multiple issues and have allocated the following additional references to parts of this issue: CVE-2011-5062, CVE-2011-5063 and CVE-2011-5064. The Apache Tomcat security team will continue to treat this as a single issue using the reference CVE-2011-1184.

The implementation of HTTP DIGEST authentication was discovered to have several weaknesses:

• replay attacks were permitted
• server nonces were not checked
• client nonce counts were not checked
• qop values were not checked
• realm values were not checked
• the server secret was hard-coded to a known string

The result of these weaknesses is that DIGEST authentication was only as secure as BASIC authentication.

This was fixed in revision 1158180.

This was identified by the Tomcat security team on 16 March 2011 and made public on 26 September 2011.

Affects: 6.0.0-6.0.32

Low: Information disclosure CVE-2011-2204

When using the MemoryUserDatabase (based on tomcat-users.xml) and creating users via JMX, an exception during the user creation process may trigger an error message in the JMX client that includes the user's password. This error message is also written to the Tomcat logs. User passwords are visible to administrators with JMX access and/or administrators with read access to the tomcat-users.xml file. Users that do not have these permissions but are able to read log files may be able to discover a user's password.

This was fixed in revision 1140071.

This was identified by Polina Genova on 14 June 2011 and made public on 27 June 2011.

Affects: 6.0.0-6.0.32

Low: Information disclosure CVE-2011-2526

Tomcat provides support for sendfile with the HTTP NIO and HTTP APR connectors. sendfile is used automatically for content served via the DefaultServlet and deployed web applications may use it directly via setting request attributes. These request attributes were not validated. When running under a security manager, this lack of validation allowed a malicious web application to do one or more of the following that would normally be prevented by a security manager:

• return files to users that the security manager should make inaccessible
• terminate (via a crash) the JVM

Additionally, these vulnerabilities only occur when all of the following are true:

• untrusted web applications are being used
• the SecurityManager is used to limit the untrusted web applications
• the HTTP NIO or HTTP APR connector is used
• sendfile is enabled for the connector (this is the default)

This was fixed in revision 1146703.

This was identified by the Tomcat security team on 7 July 2011 and made public on 13 July 2011.

Affects: 6.0.0-6.0.32

Important: Information disclosure CVE-2011-2729

Due to a bug in the capabilities code, jsvc (the service wrapper for Linux that is part of the Commons Daemon project) does not drop capabilities allowing the application to access files and directories owned by superuser. This vulnerability only occurs when all of the following are true:

• Tomcat is running on a Linux operating system
• jsvc was compiled with libcap
• -user parameter is used

Affected Tomcat versions shipped with source files for jsvc that included this vulnerability.

This was fixed in revision 1153824.

This was identified by Wilfried Weissmann on 20 July 2011 and made public on 12 August 2011.

Affects: 6.0.30-6.0.32

Note: The issue below was fixed in Apache Tomcat 6.0.31 but the release vote for the 6.0.31 release candidate did not pass. Therefore, although users must download 6.0.32 to obtain a version that includes a fix for this issue, version 6.0.31 is not included in the list of affected versions.

Important: Remote Denial Of Service CVE-2011-0534

The NIO connector expands its buffer endlessly during request line processing. That behaviour can be used for a denial of service attack using a carefully crafted request.

This was fixed in revision 1066313.

This was identified by the Tomcat security team on 27 Jan 2011 and made public on 5 Feb 2011.

Affects: 6.0.0-6.0.30

Low: Cross-site scripting CVE-2011-0013

The HTML Manager interface displayed web application provided data, such as display names, without filtering. A malicious web application could trigger script execution by an administrative user when viewing the manager pages.

This was fixed in revision 1057270.

This was identified by the Tomcat security team on 12 Nov 2010 and made public on 5 Feb 2011.

Affects: 6.0.0-6.0.29

Moderate: Cross-site scripting CVE-2010-4172

The Manager application used the user provided parameters sort and orderBy directly without filtering thereby permitting cross-site scripting.

This was fixed in revision 1037779.

This was first reported to the Tomcat security team on 15 Nov 2010 and made public on 22 Nov 2010.

Affects: 6.0.12-6.0.29

Low: SecurityManager file permission bypass CVE-2010-3718

When running under a SecurityManager, access to the file system is limited but web applications are granted read/write permissions to the work directory. This directory is used for a variety of temporary files such as the intermediate files generated when compiling JSPs to Servlets. The location of the work directory is specified by a ServletContect attribute that is meant to be read-only to web applications. However, due to a coding error, the read-only setting was not applied. Therefore, a malicious web application may modify the attribute before Tomcat applies the file permissions. This can be used to grant read/write permissions to any area on the file system which a malicious web application may then take advantage of. This vulnerability is only applicable when hosting web applications from untrusted sources such as shared hosting environments.

This was fixed in revision 1022560.

This was discovered by the Tomcat security team on 12 Oct 2010 and made public on 5 Feb 2011.

Affects: 6.0.0-6.0.29

Important: Remote Denial Of Service and Information Disclosure Vulnerability CVE-2010-2227

Several flaws in the handling of the 'Transfer-Encoding' header were found that prevented the recycling of a buffer. A remote attacker could trigger this flaw which would cause subsequent requests to fail and/or information to leak between requests. This flaw is mitigated if Tomcat is behind a reverse proxy (such as Apache httpd 2.2) as the proxy should reject the invalid transfer encoding header.

This was fixed in revision 958977.

This was first reported to the Tomcat security team on 14 Jun 2010 and made public on 9 Jul 2010.

Affects: 6.0.0-6.0.27

Note: The issue below was fixed in Apache Tomcat 6.0.27 but the release vote for the 6.0.27 release candidate did not pass. Therefore, although users must download 6.0.28 to obtain a version that includes a fix for this issue, version 6.0.27 is not included in the list of affected versions.

Low: Information disclosure in authentication headers CVE-2010-1157

The WWW-Authenticate HTTP header for BASIC and DIGEST authentication includes a realm name. If a <realm-name> element is specified for the application in web.xml it will be used. However, a <realm-name> is not specified then Tomcat will generate realm name using the code snippet request.getServerName() + ":" + request.getServerPort(). In some circumstances this can expose the local host name or IP address of the machine running Tomcat.

This was fixed in revision 936540.

This was first reported to the Tomcat security team on 31 Dec 2009 and made public on 21 Apr 2010.

Affects: 6.0.0-6.0.26

Note: These issues were fixed in Apache Tomcat 6.0.21 but the release votes for the 6.0.21, 6.0.22 and 6.0.23 release candidates did not pass. Therefore, although users must download 6.0.24 to obtain a version that includes fixes for these issues, versions 6.0.21 onwards are not included in the list of affected versions.

Low: Arbitrary file deletion and/or alteration on deploy CVE-2009-2693

When deploying WAR files, the WAR files were not checked for directory traversal attempts. This allows an attacker to create arbitrary content outside of the web root by including entries such as ../../bin/catalina.sh in the WAR.

This was fixed in revision 892815.

This was first reported to the Tomcat security team on 30 Jul 2009 and made public on 1 Mar 2010.

Affects: 6.0.0-6.0.20

Low: Insecure partial deploy after failed undeploy CVE-2009-2901

By default, Tomcat automatically deploys any directories placed in a host's appBase. This behaviour is controlled by the autoDeploy attribute of a host which defaults to true. After a failed undeploy, the remaining files will be deployed as a result of the autodeployment process. Depending on circumstances, files normally protected by one or more security constraints may be deployed without those security constraints, making them accessible without authentication. This issue only affects Windows platforms.

This was fixed in revision 892815.

This was first reported to the Tomcat security team on 30 Jul 2009 and made public on 1 Mar 2010.

Affects: 6.0.0-6.0.20 (Windows only)

Low: Unexpected file deletion in work directory CVE-2009-2902

When deploying WAR files, the WAR file names were not checked for directory traversal attempts. For example, deploying and undeploying ...war allows an attacker to cause the deletion of the current contents of the host's work directory which may cause problems for currently running applications.

This was fixed in revision 892815.

This was first reported to the Tomcat security team on 30 Jul 2009 and made public on 1 Mar 2010.

Affects: 6.0.0-6.0.20

Low: Insecure default password CVE-2009-3548

The Windows installer defaults to a blank password for the administrative user. If this is not changed during the install process, then by default a user is created with the name admin, roles admin and manager and a blank password.

This was fixed in revision 881771.

This was first reported to the Tomcat security team on 26 Oct 2009 and made public on 9 Nov 2009.

Affects: 6.0.0-6.0.20

Note: These issues were fixed in Apache Tomcat 6.0.19 but the release vote for that release candidate did not pass. Therefore, although users must download 6.0.20 to obtain a version that includes fixes for these issues, 6.0.19 is not included in the list of affected versions.

Important: Information Disclosure CVE-2008-5515

When using a RequestDispatcher obtained from the Request, the target path was normalised before the query string was removed. A request that included a specially crafted request parameter could be used to access content that would otherwise be protected by a security constraint or by locating it in under the WEB-INF directory.

This was fixed in revision 734734.

This was first reported to the Tomcat security team on 11 Dec 2008 and made public on 8 Jun 2009.

Affects: 6.0.0-6.0.18

Important: Denial of Service CVE-2009-0033

If Tomcat receives a request with invalid headers via the Java AJP connector, it does not return an error and instead closes the AJP connection. In case this connector is member of a mod_jk load balancing worker, this member will be put into an error state and will be blocked from use for approximately one minute. Thus the behaviour can be used for a denial of service attack using a carefully crafted request.

This was fixed in revision 742915.

This was first reported to the Tomcat security team on 26 Jan 2009 and made public on 3 Jun 2009.

Affects: 6.0.0-6.0.18

Low: Information disclosure CVE-2009-0580

Due to insufficient error checking in some authentication classes, Tomcat allows for the enumeration (brute force testing) of user names by supplying illegally URL encoded passwords. The attack is possible if FORM based authentication (j_security_check) is used with the MemoryRealm.

This was fixed in revision 747840.

This was first reported to the Tomcat security team on 25 Feb 2009 and made public on 3 Jun 2009.

Affects: 6.0.0-6.0.18

Low: Cross-site scripting CVE-2009-0781

The calendar application in the examples web application contains an XSS flaw due to invalid HTML which renders the XSS filtering protection ineffective.

This was fixed in revision 750924.

This was first reported to the Tomcat security team on 5 Mar 2009 and made public on 6 Mar 2009.

Affects: 6.0.0-6.0.18

Low: Information disclosure CVE-2009-0783

Bugs 29936 and 45933 allowed a web application to replace the XML parser used by Tomcat to process web.xml, context.xml and tld files. In limited circumstances these bugs may allow a rogue web application to view and/or alter the web.xml, context.xml and tld files of other web applications deployed on the Tomcat instance.

This was fixed in revisions 652592 and 739522.

This was first reported to the Tomcat security team on 2 Mar 2009 and made public on 4 Jun 2009.

Affects: 6.0.0-6.0.18

Note: These issues were fixed in Apache Tomcat 6.0.17 but the release vote for that release candidate did not pass. Therefore, although users must download 6.0.18 to obtain a version that includes fixes for these issues, 6.0.17 is not included in the list of affected versions.

Low: Cross-site scripting CVE-2008-1232

The message argument of HttpServletResponse.sendError() call is not only displayed on the error page, but is also used for the reason-phrase of HTTP response. This may include characters that are illegal in HTTP headers. It is possible for a specially crafted message to result in arbitrary content being injected into the HTTP response. For a successful XSS attack, unfiltered user supplied data must be included in the message argument.

This was fixed in revision 673834.

This was first reported to the Tomcat security team on 24 Jan 2008 and made public on 1 Aug 2008.

Affects: 6.0.0-6.0.16

Low: Cross-site scripting CVE-2008-1947

The Host Manager web application did not escape user provided data before including it in the output. This enabled a XSS attack. This application now filters the data before use. This issue may be mitigated by logging out (closing the browser) of the application once the management tasks have been completed.

This was fixed in revision 662585.

This was first reported to the Tomcat security team on 15 May 2008 and made public on 28 May 2008.

Affects: 6.0.0-6.0.16

Important: Information disclosure CVE-2008-2370

When using a RequestDispatcher the target path was normalised before the query string was removed. A request that included a specially crafted request parameter could be used to access content that would otherwise be protected by a security constraint or by locating it in under the WEB-INF directory.

This was fixed in revision 673839.

This was first reported to the Tomcat security team on 13 Jun 2008 and made public on 1 August 2008.

Affects: 6.0.0-6.0.16

Low: Session hi-jacking CVE-2007-5333

The previous fix for CVE-2007-3385 was incomplete. It did not consider the use of quotes or %5C within a cookie value.

Affects: 6.0.0-6.0.14

Low: Elevated privileges CVE-2007-5342

The JULI logging component allows web applications to provide their own logging configurations. The default security policy does not restrict this configuration and allows an untrusted web application to add files or overwrite existing files where the Tomcat process has the necessary file permissions to do so.

Affects: 6.0.0-6.0.15

Important: Information disclosure CVE-2007-5461

When Tomcat's WebDAV servlet is configured for use with a context and has been enabled for write, some WebDAV requests that specify an entity with a SYSTEM tag can result in the contents of arbitary files being returned to the client.

Affects: 6.0.0-6.0.14

Important: Data integrity CVE-2007-6286

When using the native (APR based) connector, connecting to the SSL port using netcat and then disconnecting without sending any data will cause tomcat to handle a duplicate copy of one of the recent requests.

Affects: 6.0.0-6.0.15

Important: Information disclosure CVE-2008-0002

If an exception occurs during the processing of parameters (eg if the client disconnects) then it is possible that the parameters submitted for that request will be incorrectly processed as part of a subsequent request.

Affects: 6.0.5-6.0.15

Low: Cross-site scripting CVE-2007-2449

JSPs within the examples web application did not escape user provided data before including it in the output. This enabled a XSS attack. These JSPs now filter the data before use. This issue may be mitigated by undeploying the examples web application. Note that it is recommended that the examples web application is not installed on a production system.

Affects: 6.0.0-6.0.13

Low: Cross-site scripting CVE-2007-2450

The Manager and Host Manager web applications did not escape user provided data before including it in the output. This enabled a XSS attack. These applications now filter the data before use. This issue may be mitigated by logging out (closing the browser) of the application once the management tasks have been completed.

Affects: 6.0.0-6.0.13

Low: Session hi-jacking CVE-2007-3382

Tomcat incorrectly treated a single quote character (') in a cookie value as a delimiter. In some circumstances this lead to the leaking of information such as session ID to an attacker.

Affects: 6.0.0-6.0.13

Low: Session hi-jacking CVE-2007-3385

Tomcat incorrectly handled the character sequence \" in a cookie value. In some circumstances this lead to the leaking of information such as session ID to an attacker.

Affects: 6.0.0-6.0.13

Low: Cross-site scripting CVE-2007-3386

The Host Manager Servlet did not filter user supplied data before display. This enabled an XSS attack.

Affects: 6.0.0-6.0.13

Moderate: Cross-site scripting CVE-2007-1355

The JSP and Servlet included in the sample application within the Tomcat documentation webapp did not escape user provided data before including it in the output. This enabled a XSS attack. These pages have been simplified not to use any user provided data in the output.

Affects: 6.0.0-6.0.10

Important: Information disclosure CVE-2005-2090

Requests with multiple content-length headers should be rejected as invalid. When multiple components (firewalls, caches, proxies and Tomcat) process a sequence of requests where one or more requests contain multiple content-length headers and several components do not reject the request and make different decisions as to which content-length leader to use an attacker can poision a web-cache, perform an XSS attack and obtain senstive information from requests other then their own. Tomcat now returns 400 for requests with multiple content-length headers.

Affects: 6.0.0-6.0.10

Important: Directory traversal CVE-2007-0450

Tomcat permits '\', '%2F' and '%5C' as path delimiters. When Tomcat is used behind a proxy (including, but not limited to, Apache HTTP server with mod_proxy and mod_jk) configured to only proxy some contexts, a HTTP request containing strings like "/\../" may allow attackers to work around the context restriction of the proxy, and access the non-proxied contexts.

The following Java system properties have been added to Tomcat to provide additional control of the handling of path delimiters in URLs (both options default to false):

• org.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH: true|false
• org.apache.catalina.connector.CoyoteAdapter.ALLOW_BACKSLASH: true|false

Due to the impossibility to guarantee that all URLs are handled by Tomcat as they are in proxy servers, Tomcat should always be secured as if no proxy restricting context access was used.

Affects: 6.0.0-6.0.9

Moderate: Session hi-jacking CVE-2008-0128

When using the SingleSignOn Valve via https the Cookie JSESSIONIDSSO is transmitted without the "secure" attribute, resulting in it being transmitted to any content that is - by purpose or error - requested via http from the same server.

Affects: 6.0.0-6.0.8

Low: Cross-site scripting CVE-2007-1358

Web pages that display the Accept-Language header value sent by the client are susceptible to a cross-site scripting attack if they assume the Accept-Language header value conforms to RFC 2616. Under normal circumstances this would not be possible to exploit, however older versions of Flash player were known to allow carefully crafted malicious Flash files to make requests with such custom headers. Tomcat now ignores invalid values for Accept-Language headers that do not conform to RFC 2616.

Affects: 6.0.0-6.0.5

Low: Denial Of Service CVE-2012-5568

Sending an HTTP request 1 byte at a time will consume a thread from the connection pool until the request has been fully processed if using the BIO or APR/native HTTP connectors. Multiple requests may be used to consume all threads in the connection pool thereby creating a denial of service.

Since the relationship between the client side resources and server side resources is a linear one, this issue is not something that the Tomcat Security Team views as a vulnerability. This is a generic DoS problem and there is no magic solution. This issue has been discussed several times on the Tomcat mailing lists. The best place to start to review these discussions is the report for bug 54236.

This was first discussed on the public Tomcat users mailing list on 19 June 2009.

Important: Remote Denial Of Service CVE-2010-4476

A JVM bug could cause Double conversion to hang JVM when accessing to a form based security constrained page or any page that calls javax.servlet.ServletRequest.getLocale() or javax.servlet.ServletRequest.getLocales(). A specially crafted request can be used to trigger a denial of service.

A work-around for this JVM bug was provided in revision 1066315. This work-around is included in Tomcat 6.0.32 onwards.

This was first reported to the Tomcat security team on 01 Feb 2011 and made public on 31 Jan 2011.

Affects: 6.0.0-6.0.31

Moderate: TLS SSL Man In The Middle CVE-2009-3555

A vulnerability exists in the TLS protocol that allows an attacker to inject arbitrary requests into an TLS stream during renegotiation.

The TLS implementation used by Tomcat varies with connector. The blocking IO (BIO) and non-blocking (NIO) connectors use the JSSE implementation provided by the JVM. The APR/native connector uses OpenSSL.

The BIO connector is vulnerable if the JSSE version used is vulnerable. To workaround this until a fix is available in JSSE, a new connector attribute allowUnsafeLegacyRenegotiation has been added to the BIO connector. It should be set to false (the default) to protect against this vulnerability.

The NIO connector is not vulnerable as it does not support renegotiation.

The APR/native workarounds are detailed on the APR/native connector security page.

Users should be aware that the impact of disabling renegotiation will vary with both application and client. In some circumstances disabling renegotiation may result in some clients being unable to access the application.

A workaround was implemented in revision 881774 and revision 891292 that provided the new allowUnsafeLegacyRenegotiation attribute. This work around is included in Tomcat 6.0.21 onwards.

Support for the new TLS renegotiation protocol (RFC 5746) that does not have this security issue:

• For connectors using JSSE implementation provided by JVM: Added in Tomcat 6.0.32.
  Requires JRE that supports RFC 5746. For Oracle JRE that is known to be 6u22 or later.
• For connectors using APR and OpenSSL:
  TBD. See APR/native connector security page.

Important: Directory traversal CVE-2008-2938

Originally reported as a Tomcat vulnerability the root cause of this issue is that the JVM does not correctly decode UTF-8 encoded URLs to UTF-8. This exposes a directory traversal vulnerability when the connector uses URIEncoding="UTF-8". This directory traversal is limited to the docBase of the web application.

If a context is configured with allowLinking="true" then the directory traversal vulnerability is extended to the entire file system of the host server.

It should also be noted that setting useBodyEncodingForURI="true" has the same effect as setting URIEncoding="UTF-8" when processing requests with bodies encoded with UTF-8.

Although the root cause was quickly identified as a JVM issue and that it affected multiple JVMs from multiple vendors, it was decided to report this as a Tomcat vulnerability until such time as the JVM vendors provided updates to resolve this issue. For further information on the status of this issue for your JVM, contact your JVM vendor.

A workaround was implemented in revision 678137 that protects against this and any similar character encoding issues that may still exist in the JVM. This work around is included in Tomcat 6.0.18 onwards.