CVE-2011-4862 Memory corruption in n/a

What is CVE-2011-4862?

CVE-2011-4862 is a critical memory corruption vulnerability in Debian Debian Linux, published on 25 Dec 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-120

Which versions are affected by CVE-2011-4862?

It affects 10 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Freebsd Freebsd, Gnu Inetutils, Heimdal Project Heimdal, Mit Krb5-Appl and 4 more.

How do I fix CVE-2011-4862?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2011-4862 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2011-4862 exists.

Public exploit code: 3 Metasploit modules, 3 Exploit-DB entries and 3 proofs of concept on GitHub.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2011-4862, DSA-2372-1, DSA-2373-1, DSA-2375-1, GHSA-x8cr-m6vm-pqh4, RHSA-2011:1851 and 3 more.