CVE-2011-4601
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedfamily_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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe oscar protocol plugin in libpurple (Pidgin) fails to perform UTF-8 validation on message data in family_feedbag.c. This allows remote attackers sending crafted AIM or ICQ messages associated with buddy-list addition to trigger an application crash via malformed UTF-8 sequences.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data<= 2.10.0= 2.0.0= 2.0.1= 2.0.2= 2.1.0= 2.1.1= 2.2.0= 2.2.1= 2.2.2= 2.3.0= 2.3.1= 2.4.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Authentication
- None
- Confidentiality
- None
- Integrity
- None
- Availability
- Partial
AV:N/AC:L/Au:N/C:N/I:N/A:P
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Verify Pidgin is installedRun `pidgin --version` or check your package manager for an installed pidgin packageAffected if Pidgin is not installed, then not affected
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Check installed Pidgin versionRun `pidgin --version` to get the exact version number, or query your system's package manager (e.g., `dpkg -l pidgin` or `rpm -q pidgin`)Affected if Version is 2.10.0 or lower (including 2.0.0, 2.0.1, 2.0.2, 2.1.0, 2.1.1, 2.2.0, 2.2.1, 2.2.2, 2.3.0, 2.3.1, 2.4.0) - these versions contain the vulnerable oscar protocol plugin code in family_feedbag.c
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Check for active AIM or ICQ accountsInspect Pidgin account configuration (typically ~/.purple/accounts.xml) or open Pidgin and navigate to Accounts > Manage Accounts to see if any AIM or ICQ protocols are enabledAffected if AIM or ICQ accounts exist and are enabled, the oscar protocol plugin will process incoming messages and the vulnerability can be triggered
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Confirm oscar protocol plugin is loadedCheck that the oscar protocol module (liboscar.so or similar) exists in the Pidgin plugin directory (usually /usr/lib/pidgin/ or /usr/lib64/pidgin/)Affected if The oscar protocol plugin is present and being used, it will handle AIM/ICQ messages without proper UTF-8 validation on buddy-list related messages
You are affected if Pidgin version 2.10.0 or lower is installed AND you have active AIM or ICQ accounts, as the oscar protocol plugin will process buddy-list messages without UTF-8 validation and can crash upon receiving malformed UTF-8 sequences.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpgrade Pidgin to version 2.10.1 or later which includes proper UTF-8 validation in the oscar protocol plugin.
- Consultation1.0 h
- Implementation1.0 h
- Testing1.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2011-4601 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2011-4601 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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