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CVE-2011-4862

Published
Dec 25, 2011
Updated
Apr 10, 2026
Affected
0 pkgs
Patched
None yet
Exploits
10 known

EPSS Exploitation Probability

via FIRST.org ↗
95.1%probability of exploitation in next 30 days
Very High Risk100th percentile0.00%
91.8%93.2%94.5%95.9%92.6%95.1%Jan 26May 26Jul 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT Kerberos Version 5 Applications (aka krb5-appl) 1.0.2 and earlier, Heimdal 1.5.1 and earlier, GNU inetutils, and possibly other products allows remote attackers to execute arbitrary code via a long encryption key, as exploited in the wild in December 2011.

Exploits & PoCs
10

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-18280remotelinux✓ Verified

TelnetD encrypt_keyid - Function Pointer Overwrite

by NighterMan & BatchDrake · Dec 26, 2011

EDB-18369remotebsd✓ Verified

FreeBSD - Telnet Service Encryption Key ID Buffer Overflow (Metasploit)

by Metasploit · Jan 14, 2012

EDB-18368remotelinux✓ Verified

Linux BSD-derived Telnet Service Encryption Key ID - Remote Buffer Overflow (Metasploit)

by Metasploit · Jan 14, 2012

Detection & mitigation playbook

Vulnerability
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Remediation status

    No patched version of the affected component has shipped for CVE-2011-4862 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.

  3. Mitigate without a patch

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether CVE-2011-4862 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2011-4862. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT Kerberos Version 5 Applications (aka krb5-appl) 1.0.2 and earlier, Heimdal 1.5.1 and earlier, GNU inetutils, and possibly other products allows remote attackers to execute arbitrary code via a long encryption key, as exploited in the wild in December 2011.
O3 Security · Impact-Aware SCA

Is CVE-2011-4862 in your dependencies?

O3 detects CVE-2011-4862 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.