protocols/jabber/auth.c in libpurple in Pidgin 2.6.0, and possibly other versions, does not follow the "require TLS/SSL" preference when connecting to older Jabber servers that do not follow the XMPP specification, which causes libpurple to connect to the server without the expected encryption and allows remote attackers to sniff sessions.

From Red Hat Security Advisory 2009:1453 :

Updated pidgin packages that fix several security issues are now available for Red Hat Enterprise Linux 4 and 5.

This update has been rated as having moderate security impact by the Red Hat Security Response Team.

Pidgin is an instant messaging program which can log in to multiple accounts on multiple instant messaging networks simultaneously.
Info/Query (IQ) is an Extensible Messaging and Presence Protocol (XMPP) specific request-response mechanism.

A NULL pointer dereference flaw was found in the way the Pidgin XMPP protocol plug-in processes IQ error responses when trying to fetch a custom smiley. A remote client could send a specially crafted IQ error response that would crash Pidgin. (CVE-2009-3085)

A NULL pointer dereference flaw was found in the way the Pidgin IRC protocol plug-in handles IRC topics. A malicious IRC server could send a specially crafted IRC TOPIC message, which once received by Pidgin, would lead to a denial of service (Pidgin crash). (CVE-2009-2703)

It was discovered that, when connecting to certain, very old Jabber servers via XMPP, Pidgin may ignore the 'Require SSL/TLS' setting. In these situations, a non-encrypted connection is established rather than the connection failing, causing the user to believe they are using an encrypted connection when they are not, leading to sensitive information disclosure (session sniffing). (CVE-2009-3026)

A NULL pointer dereference flaw was found in the way the Pidgin MSN protocol plug-in handles improper MSNSLP invitations. A remote attacker could send a specially crafted MSNSLP invitation request, which once accepted by a valid Pidgin user, would lead to a denial of service (Pidgin crash). (CVE-2009-3083)

These packages upgrade Pidgin to version 2.6.2. Refer to the Pidgin release notes for a full list of changes:
http://developer.pidgin.im/wiki/ChangeLog

All Pidgin users should upgrade to these updated packages, which correct these issues. Pidgin must be restarted for this update to take effect.

From Red Hat Security Advisory 2009:1218 :

Updated pidgin packages that fix a security issue are now available for Red Hat Enterprise Linux 3, 4, and 5.

This update has been rated as having critical security impact by the Red Hat Security Response Team.

Pidgin is an instant messaging program which can log in to multiple accounts on multiple instant messaging networks simultaneously.

Federico Muttis of Core Security Technologies discovered a flaw in Pidgin's MSN protocol handler. If a user received a malicious MSN message, it was possible to execute arbitrary code with the permissions of the user running Pidgin. (CVE-2009-2694)

Note: Users can change their privacy settings to only allow messages from users on their buddy list to limit the impact of this flaw.

These packages upgrade Pidgin to version 2.5.9. Refer to the Pidgin release notes for a full list of changes:
http://developer.pidgin.im/wiki/ChangeLog

All Pidgin users should upgrade to these updated packages, which resolve this issue. Pidgin must be restarted for this update to take effect.

CVE-2009-3026 pidgin: ignores SSL/TLS requirements with old jabber servers

CVE-2009-2703 Pidgin: NULL pointer dereference by handling IRC topic(s) (DoS)

CVE-2009-3083 Pidgin: NULL pointer dereference by processing incomplete MSN SLP invite (DoS)

CVE-2009-3085 Pidgin: NULL pointer dereference by processing a custom smiley (DoS)

A NULL pointer dereference flaw was found in the way the Pidgin XMPP protocol plug-in processes IQ error responses when trying to fetch a custom smiley. A remote client could send a specially crafted IQ error response that would crash Pidgin. (CVE-2009-3085)

A NULL pointer dereference flaw was found in the way the Pidgin IRC protocol plug-in handles IRC topics. A malicious IRC server could send a specially crafted IRC TOPIC message, which once received by Pidgin, would lead to a denial of service (Pidgin crash). (CVE-2009-2703)

It was discovered that, when connecting to certain, very old Jabber servers via XMPP, Pidgin may ignore the 'Require SSL/TLS' setting. In these situations, a non-encrypted connection is established rather than the connection failing, causing the user to believe they are using an encrypted connection when they are not, leading to sensitive information disclosure (session sniffing). (CVE-2009-3026)

A NULL pointer dereference flaw was found in the way the Pidgin MSN protocol plug-in handles improper MSNSLP invitations. A remote attacker could send a specially crafted MSNSLP invitation request, which once accepted by a valid Pidgin user, would lead to a denial of service (Pidgin crash). (CVE-2009-3083)

Pidgin must be restarted for this update to take effect.

This update of pidgin fixes the following issues :

  - Allowed to send confidential data unencrypted even if     SSL was chosen by user. (CVE-2009-3026: CVSS v2 Base     Score: 5.0)

  - Remote denial of service in yahoo IM plug-in.
    (CVE-2009-3025: CVSS v2 Base Score: 4.3)

  - Remote denial of service in MSN plug-in. (CVE-2009-3083:
    CVSS v2 Base Score: 5.0)

  - Remote denial of service in MSN plug-in. (CVE-2009-3084:
    CVSS v2 Base Score: 5.0)

  - Remote denial of service in XMPP plug-in.
    (CVE-2009-3085: CVSS v2 Base Score: 5.0)

  - Remote denial of service in ICQ plug-in. (CVE-2009-3615:
    CVSS v2 Base Score: 5.0)

  - QQ protocol upgrade Migrate all QQ accounts to QQ2008.

It was discovered that Pidgin did not properly handle certain topic messages in the IRC protocol handler. If a user were tricked into connecting to a malicious IRC server, an attacker could cause Pidgin to crash, leading to a denial of service. This issue only affected Ubuntu 8.04 LTS, Ubuntu 8.10 and Ubuntu 9.04. (CVE-2009-2703)

It was discovered that Pidgin did not properly enforce the 'require TLS/SSL' setting when connecting to certain older Jabber servers. If a remote attacker were able to perform a man-in-the-middle attack, this flaw could be exploited to view sensitive information. This issue only affected Ubuntu 8.04 LTS, Ubuntu 8.10 and Ubuntu 9.04. (CVE-2009-3026)

It was discovered that Pidgin did not properly handle certain SLP invite messages in the MSN protocol handler. A remote attacker could send a specially crafted invite message and cause Pidgin to crash, leading to a denial of service. This issue only affected Ubuntu 8.04 LTS, Ubuntu 8.10 and Ubuntu 9.04. (CVE-2009-3083)

It was discovered that Pidgin did not properly handle certain errors in the XMPP protocol handler. A remote attacker could send a specially crafted message and cause Pidgin to crash, leading to a denial of service. This issue only affected Ubuntu 8.10 and Ubuntu 9.04.
(CVE-2009-3085)

It was discovered that Pidgin did not properly handle malformed contact-list data in the OSCAR protocol handler. A remote attacker could send specially crafted contact-list data and cause Pidgin to crash, leading to a denial of service. (CVE-2009-3615)

It was discovered that Pidgin did not properly handle custom smiley requests in the MSN protocol handler. A remote attacker could send a specially crafted filename in a custom smiley request and obtain arbitrary files via directory traversal. This issue only affected Ubuntu 8.10, Ubuntu 9.04 and Ubuntu 9.10. (CVE-2010-0013)

Pidgin for Ubuntu 8.04 LTS was also updated to fix connection issues with the MSN protocol.

USN-675-1 and USN-781-1 provided updated Pidgin packages to fix multiple security vulnerabilities in Ubuntu 8.04 LTS. The security patches to fix CVE-2008-2955 and CVE-2009-1376 were incomplete. This update corrects the problem. 

It was discovered that Pidgin did not properly handle file transfers containing a long filename and special characters in the MSN protocol handler. A remote attacker could send a specially crafted filename in a file transfer request and cause Pidgin to crash, leading to a denial of service. (CVE-2008-2955)

It was discovered that Pidgin did not properly handle certain malformed messages in the MSN protocol handler. A remote attacker could send a specially crafted message and possibly execute arbitrary code with user privileges.
(CVE-2009-1376).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Updated pidgin packages that fix several security issues are now available for Red Hat Enterprise Linux 4 and 5.

This update has been rated as having moderate security impact by the Red Hat Security Response Team.

Pidgin is an instant messaging program which can log in to multiple accounts on multiple instant messaging networks simultaneously.
Info/Query (IQ) is an Extensible Messaging and Presence Protocol (XMPP) specific request-response mechanism.

A NULL pointer dereference flaw was found in the way the Pidgin XMPP protocol plug-in processes IQ error responses when trying to fetch a custom smiley. A remote client could send a specially crafted IQ error response that would crash Pidgin. (CVE-2009-3085)

A NULL pointer dereference flaw was found in the way the Pidgin IRC protocol plug-in handles IRC topics. A malicious IRC server could send a specially crafted IRC TOPIC message, which once received by Pidgin, would lead to a denial of service (Pidgin crash). (CVE-2009-2703)

It was discovered that, when connecting to certain, very old Jabber servers via XMPP, Pidgin may ignore the 'Require SSL/TLS' setting. In these situations, a non-encrypted connection is established rather than the connection failing, causing the user to believe they are using an encrypted connection when they are not, leading to sensitive information disclosure (session sniffing). (CVE-2009-3026)

A NULL pointer dereference flaw was found in the way the Pidgin MSN protocol plug-in handles improper MSNSLP invitations. A remote attacker could send a specially crafted MSNSLP invitation request, which once accepted by a valid Pidgin user, would lead to a denial of service (Pidgin crash). (CVE-2009-3083)

These packages upgrade Pidgin to version 2.6.2. Refer to the Pidgin release notes for a full list of changes:
http://developer.pidgin.im/wiki/ChangeLog

All Pidgin users should upgrade to these updated packages, which correct these issues. Pidgin must be restarted for this update to take effect.

This update of pidgin fixes the following issues :

  - CVE-2009-3026: CVSS v2 Base Score: 5.0 Allowed to send     confidential data unencrypted even if SSL was chosen by     user.

  - CVE-2009-3025: CVSS v2 Base Score: 4.3 Remote denial of     service in yahoo IM plug-in.

  - CVE-2009-3083: CVSS v2 Base Score: 5.0 Remote denial of     service in MSN plug-in.

  - CVE-2009-3084: CVSS v2 Base Score: 5.0 Remote denial of     service in MSN plug-in.

  - CVE-2009-3085: CVSS v2 Base Score: 5.0 Remote denial of     service in XMPP plug-in.

  - CVE-2009-3615: CVSS v2 Base Score: 5.0 Remote denial of     service in ICQ plug-in.

  - QQ protocol upgrade Migrate all QQ accounts to QQ2008.

Security vulnerabilities has been identified and fixed in pidgin :

The NSS plugin in libpurple in Pidgin 2.4.1 does not verify SSL certificates, which makes it easier for remote attackers to trick a user into accepting an invalid server certificate for a spoofed service. (CVE-2008-3532)

Pidgin 2.4.1 allows remote attackers to cause a denial of service (crash) via a long filename that contains certain characters, as demonstrated using an MSN message that triggers the crash in the msn_slplink_process_msg function. (CVE-2008-2955)

The UPnP functionality in Pidgin 2.0.0, and possibly other versions, allows remote attackers to trigger the download of arbitrary files and cause a denial of service (memory or disk consumption) via a UDP packet that specifies an arbitrary URL. (CVE-2008-2957)

Buffer overflow in the XMPP SOCKS5 bytestream server in Pidgin (formerly Gaim) before 2.5.6 allows remote authenticated users to execute arbitrary code via vectors involving an outbound XMPP file transfer. NOTE: some of these details are obtained from third-party information (CVE-2009-1373).

Buffer overflow in the decrypt_out function in Pidgin (formerly Gaim) before 2.5.6 allows remote attackers to cause a denial of service (application crash) via a QQ packet (CVE-2009-1374).

The PurpleCircBuffer implementation in Pidgin (formerly Gaim) before 2.5.6 does not properly maintain a certain buffer, which allows remote attackers to cause a denial of service (memory corruption and application crash) via vectors involving the (1) XMPP or (2) Sametime protocol (CVE-2009-1375).

Multiple integer overflows in the msn_slplink_process_msg functions in the MSN protocol handler in (1) libpurple/protocols/msn/slplink.c and (2) libpurple/protocols/msnp9/slplink.c in Pidgin (formerly Gaim) before 2.5.6 on 32-bit platforms allow remote attackers to execute arbitrary code via a malformed SLP message with a crafted offset value, leading to buffer overflows. NOTE: this issue exists because of an incomplete fix for CVE-2008-2927 (CVE-2009-1376).

The OSCAR protocol implementation in Pidgin before 2.5.8 misinterprets the ICQWebMessage message type as the ICQSMS message type, which allows remote attackers to cause a denial of service (application crash) via a crafted ICQ web message that triggers allocation of a large amount of memory (CVE-2009-1889).

The msn_slplink_process_msg function in libpurple/protocols/msn/slplink.c in libpurple, as used in Pidgin (formerly Gaim) before 2.5.9 and Adium 1.3.5 and earlier, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) by sending multiple crafted SLP (aka MSNSLP) messages to trigger an overwrite of an arbitrary memory location. NOTE: this issue reportedly exists because of an incomplete fix for CVE-2009-1376 (CVE-2009-2694).

Unspecified vulnerability in Pidgin 2.6.0 allows remote attackers to cause a denial of service (crash) via a link in a Yahoo IM (CVE-2009-3025)

protocols/jabber/auth.c in libpurple in Pidgin 2.6.0, and possibly other versions, does not follow the require TLS/SSL preference when connecting to older Jabber servers that do not follow the XMPP specification, which causes libpurple to connect to the server without the expected encryption and allows remote attackers to sniff sessions (CVE-2009-3026).

libpurple/protocols/irc/msgs.c in the IRC protocol plugin in libpurple in Pidgin before 2.6.2 allows remote IRC servers to cause a denial of service (NULL pointer dereference and application crash) via a TOPIC message that lacks a topic string (CVE-2009-2703).

The msn_slp_sip_recv function in libpurple/protocols/msn/slp.c in the MSN protocol plugin in libpurple in Pidgin before 2.6.2 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via an SLP invite message that lacks certain required fields, as demonstrated by a malformed message from a KMess client (CVE-2009-3083).

The msn_slp_process_msg function in libpurple/protocols/msn/slpcall.c in the MSN protocol plugin in libpurple 2.6.0 and 2.6.1, as used in Pidgin before 2.6.2, allows remote attackers to cause a denial of service (application crash) via a handwritten (aka Ink) message, related to an uninitialized variable and the incorrect UTF16-LE charset name (CVE-2009-3084).

The XMPP protocol plugin in libpurple in Pidgin before 2.6.2 does not properly handle an error IQ stanza during an attempted fetch of a custom smiley, which allows remote attackers to cause a denial of service (application crash) via XHTML-IM content with cid: images (CVE-2009-3085).

This update provides pidgin 2.6.2, which is not vulnerable to these issues.

This update of pidgin fixes the following issues :

  - Allowed to send confidential data unencrypted even if     SSL was chosen by user. (CVE-2009-3026: CVSS v2 Base     Score: 5.0)

  - Remote denial of service in yahoo IM plug-in.
    (CVE-2009-3025: CVSS v2 Base Score: 4.3)

  - Remote denial of service in MSN plug-in. (CVE-2009-3083:
    CVSS v2 Base Score: 5.0)

  - Remote denial of service in MSN plug-in. (CVE-2009-3084:
    CVSS v2 Base Score: 5.0)

  - Remote denial of service in XMPP plug-in.
    (CVE-2009-3085: CVSS v2 Base Score: 5.0)

  - Remote denial of service in ICQ plug-in. (CVE-2009-3615:
    CVSS v2 Base Score: 5.0)

The remote host is affected by the vulnerability described in GLSA-200910-02 (Pidgin: Multiple vulnerabilities)

    Multiple vulnerabilities were found in Pidgin:
    Yuriy     Kaminskiy reported that the OSCAR protocol implementation in Pidgin     misinterprets the ICQWebMessage message type as the ICQSMS message     type, triggering an allocation of a large amount of memory     (CVE-2009-1889).
    Federico Muttis of Core Security Technologies     reported that the msn_slplink_process_msg() function in     libpurple/protocols/msn/slplink.c in libpurple as used in Pidgin     doesn't properly process incoming SLP messages, triggering an overwrite     of an arbitrary memory location (CVE-2009-2694). NOTE: This issue     reportedly exists because of an incomplete fix for CVE-2009-1376 (GLSA     200905-07).
    bugdave reported that protocols/jabber/auth.c in     libpurple as used in Pidgin does not follow the 'require TSL/SSL'     preference when connecting to older Jabber servers that do not follow     the XMPP specification, resulting in a connection to the server without     the expected encryption (CVE-2009-3026).
  Impact :

    A remote attacker could send specially crafted SLP (via MSN) or ICQ web     messages, possibly leading to execution of arbitrary code with the     privileges of the user running Pidgin, unauthorized information     disclosure, or a Denial of Service.
  Workaround :

    There is no known workaround at this time.

The version of Pidgin installed on the remote host is earlier than 2.6.1.  Such versions are reportedly affected by one or more of following issues :

  - The Yahoo protocol plugin may crash when receiving an IM     from any user that contains a URL. (CVE-2009-3025)

  - The XMPP protocol plugin can be tricked into establishing     an insecure connection by a malicious man-in-the-middle by     causing libpurple to use the older IQ-based login and then     not offering TLS/SSL. (CVE-2009-3026)

Security vulnerabilities has been identified and fixed in pidgin :

The msn_slplink_process_msg function in libpurple/protocols/msn/slplink.c in libpurple, as used in Pidgin (formerly Gaim) before 2.5.9 and Adium 1.3.5 and earlier, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) by sending multiple crafted SLP (aka MSNSLP) messages to trigger an overwrite of an arbitrary memory location. NOTE: this issue reportedly exists because of an incomplete fix for CVE-2009-1376 (CVE-2009-2694).

Unspecified vulnerability in Pidgin 2.6.0 allows remote attackers to cause a denial of service (crash) via a link in a Yahoo IM (CVE-2009-3025)

protocols/jabber/auth.c in libpurple in Pidgin 2.6.0, and possibly other versions, does not follow the require TLS/SSL preference when connecting to older Jabber servers that do not follow the XMPP specification, which causes libpurple to connect to the server without the expected encryption and allows remote attackers to sniff sessions (CVE-2009-3026).

libpurple/protocols/irc/msgs.c in the IRC protocol plugin in libpurple in Pidgin before 2.6.2 allows remote IRC servers to cause a denial of service (NULL pointer dereference and application crash) via a TOPIC message that lacks a topic string (CVE-2009-2703).

The msn_slp_sip_recv function in libpurple/protocols/msn/slp.c in the MSN protocol plugin in libpurple in Pidgin before 2.6.2 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via an SLP invite message that lacks certain required fields, as demonstrated by a malformed message from a KMess client (CVE-2009-3083).

The msn_slp_process_msg function in libpurple/protocols/msn/slpcall.c in the MSN protocol plugin in libpurple 2.6.0 and 2.6.1, as used in Pidgin before 2.6.2, allows remote attackers to cause a denial of service (application crash) via a handwritten (aka Ink) message, related to an uninitialized variable and the incorrect UTF16-LE charset name (CVE-2009-3084).

The XMPP protocol plugin in libpurple in Pidgin before 2.6.2 does not properly handle an error IQ stanza during an attempted fetch of a custom smiley, which allows remote attackers to cause a denial of service (application crash) via XHTML-IM content with cid: images (CVE-2009-3085).

This update provides pidgin 2.6.2, which is not vulnerable to these issues.

The remote host is running Pidgin < 2.6.1. Such versions are potentially affected by multiple issues : 

  - A denial-of-service vulnerability because it fails to properly handle malformed links sent via the Yahoo Instant Messenger protocol. (CVE-2009-3025)

  - A man-in-the-middle vulnerability exists because the application does not require the TLS/SSL preference to be enabled when connecting to older Jabber servers. (CVE-2009-3026)

Updated pidgin packages that fix a security issue are now available for Red Hat Enterprise Linux 3, 4, and 5.

This update has been rated as having critical security impact by the Red Hat Security Response Team.

Pidgin is an instant messaging program which can log in to multiple accounts on multiple instant messaging networks simultaneously.

Federico Muttis of Core Security Technologies discovered a flaw in Pidgin's MSN protocol handler. If a user received a malicious MSN message, it was possible to execute arbitrary code with the permissions of the user running Pidgin. (CVE-2009-2694)

Note: Users can change their privacy settings to only allow messages from users on their buddy list to limit the impact of this flaw.

These packages upgrade Pidgin to version 2.5.9. Refer to the Pidgin release notes for a full list of changes:
http://developer.pidgin.im/wiki/ChangeLog

All Pidgin users should upgrade to these updated packages, which resolve this issue. Pidgin must be restarted for this update to take effect.

ID	Name	Product	Family	Severity
67928	Oracle Linux 4 : pidgin (ELSA-2009-1453)	Nessus	Oracle Linux Local Security Checks	medium
67912	Oracle Linux 3 / 4 : pidgin (ELSA-2009-1218)	Nessus	Oracle Linux Local Security Checks	critical
60668	Scientific Linux Security Update : pidgin on SL4.x, SL5.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	medium
51726	SuSE 10 Security Update : pidgin (ZYPP Patch Number 6710)	Nessus	SuSE Local Security Checks	medium
51725	SuSE 10 Security Update : pidgin (ZYPP Patch Number 6709)	Nessus	SuSE Local Security Checks	medium
44057	Ubuntu 8.04 LTS / 8.10 / 9.04 / 9.10 : pidgin vulnerabilities (USN-886-1)	Nessus	Ubuntu Local Security Checks	critical
43793	CentOS 4 / 5 : pidgin (CESA-2009:1453)	Nessus	CentOS Local Security Checks	medium
43054	openSUSE Security Update : finch (finch-1625)	Nessus	SuSE Local Security Checks	medium
43052	openSUSE Security Update : finch (finch-1625)	Nessus	SuSE Local Security Checks	medium
43050	openSUSE Security Update : finch (finch-1625)	Nessus	SuSE Local Security Checks	medium
43024	Mandriva Linux Security Advisory : pidgin (MDVSA-2009:321)	Nessus	Mandriva Local Security Checks	critical
42989	SuSE 11 Security Update : pidgin (SAT Patch Number 1604)	Nessus	SuSE Local Security Checks	medium
42214	GLSA-200910-02 : Pidgin: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	critical
41032	RHEL 4 / 5 : pidgin (RHSA-2009:1453)	Nessus	Red Hat Local Security Checks	medium
40986	Pidgin < 2.6.1 Multiple Vulnerabilities	Nessus	Windows	medium
40966	Mandriva Linux Security Advisory : pidgin (MDVSA-2009:230)	Nessus	Mandriva Local Security Checks	critical
5168	Pidgin < 2.6.1 Multiple Vulnerabilities	Nessus Network Monitor	Internet Messengers	medium
40639	RHEL 3 / 4 / 5 : pidgin (RHSA-2009:1218)	Nessus	Red Hat Local Security Checks	critical
40625	CentOS 3 / 5 : pidgin (CESA-2009:1218)	Nessus	CentOS Local Security Checks	critical

Detections

Analytics

CVE-2009-3026

high

Tenable Plugins

medium

critical

medium

medium

medium

critical

medium

medium

medium

medium

critical

medium

critical

medium

medium

critical

medium

critical

critical