CVE-2011-4601

CVE-2011-4601 is a medium-severity vulnerability in Pidgin with a CVSS 2.0 base score of 5.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

• Severity: Medium (CVSS 2.0 base score 5.0)
• EPSS exploit prediction: 5% (91st percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Pidgin
• Published: 2011-12-25
• Last modified: 2026-06-16

Description

family_feedbag.c in the oscar protocol plugin in libpurple in Pidgin before 2.10.1 does not perform the expected UTF-8 validation on message data, which allows remote attackers to cause a denial of service (application crash) via a crafted (1) AIM or (2) ICQ message associated with buddy-list addition.

Frequently asked questions

What is CVE-2011-4601?

family_feedbag.c in the oscar protocol plugin in libpurple in Pidgin before 2.10.1 does not perform the expected UTF-8 validation on message data, which allows remote attackers to cause a denial of service (application crash) via a crafted (1) AIM or (2) ICQ message associated with buddy-list addition.

How severe is CVE-2011-4601?

CVE-2011-4601 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2011-4601 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4601?

CVE-2011-4601 primarily affects Pidgin. In total, 45 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4601?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2011-4601 published?

CVE-2011-4601 was published on 2011-12-25 and last updated on 2026-06-16.

References

• http://developer.pidgin.im/viewmtn/revision/diff/bc79b1bf09dcfa1d8edac86a06761fce7416e69c/with/757272a78a8ca6027d518e614712c3399e34dda3/libpurple/protocols/oscar/family_feedbag.c
• http://developer.pidgin.im/viewmtn/revision/info/757272a78a8ca6027d518e614712c3399e34dda3
• http://pidgin.im/news/security/?id=57
• http://secunia.com/advisories/47219
• http://secunia.com/advisories/47234
• http://www.mandriva.com/security/advisories?name=MDVSA-2011:183
• http://www.openwall.com/lists/oss-security/2011/12/10/1
• http://www.openwall.com/lists/oss-security/2011/12/10/2
• http://www.redhat.com/support/errata/RHSA-2011-1820.html
• http://www.redhat.com/support/errata/RHSA-2011-1821.html
• http://www.securityfocus.com/bid/51010
• https://hermes.opensuse.org/messages/13195955
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A18408

Affected products (45)

• cpe:2.3:a:pidgin:pidgin:*:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.2.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.2.2:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.3.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.3.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.4.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.4.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.4.2:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.4.3:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.2:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.3:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.4:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.5:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.6:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.7:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.8:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.5.9:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.0:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.2:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.3:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.4:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.5:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.6.6:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.1:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.2:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.3:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.4:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.5:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.6:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.7:*:*:*:*:*:*:*
• cpe:2.3:a:pidgin:pidgin:2.7.8:*:*:*:*:*:*:*

More vulnerabilities in Pidgin

• CVE-2013-6490 — Critical (CVSS 10.0): The SIMPLE protocol functionality in Pidgin before 2.10.8 allows remote attackers to have an unspecified impact via a…
• CVE-2009-2694 — Critical (CVSS 10.0): The msn_slplink_process_msg function in libpurple/protocols/msn/slplink.c in libpurple, as used in Pidgin (formerly…
• CVE-2016-1000030 — Critical (CVSS 9.8): Pidgin version <2.11.0 contains a vulnerability in X.509 Certificates imports specifically due to improper check of…
• CVE-2013-6486 — Critical (CVSS 9.3): gtkutils.c in Pidgin before 2.10.8 on Windows allows user-assisted remote attackers to execute arbitrary programs via a…
• CVE-2011-3185 — Critical (CVSS 9.3): gtkutils.c in Pidgin before 2.10.0 on Windows allows user-assisted remote attackers to execute arbitrary programs via a…
• CVE-2009-1376 — Critical (CVSS 9.3): Multiple integer overflows in the msn_slplink_process_msg functions in the MSN protocol handler in (1)…

All CVEs affecting Pidgin →

Other CWE-20 (Improper Input Validation) vulnerabilities

• CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
• CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
• CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
• CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
• CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
• CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →