HOME VULNERABILITIESCVE-2011-4862

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CVE-2011-4862

CWE-120Published: December 25, 2011· Updated: Jun 16, 2026

10.0

CVSS v3.1

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.

Technical Analysis

CVE-2011-4862 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A proof-of-concept (PoC) exploit exists for CVE-2011-4862. While not yet confirmed in active campaigns, the availability of PoC code increases exploitation risk substantially.

CVSS v3.1 Vector Breakdown

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges Req.

User Interaction

Scope

Impact

ConfidentialityC

IntegrityC

AvailabilityC

AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected Vendors & Products

Debian1 product(s)

debian linux

Fedora1 product(s)

fedora

freebsd1 product(s)

freebsd

gnu1 product(s)

inetutils

heimdal_project1 product(s)

heimdal

mit1 product(s)

krb5-appl

openSUSE1 product(s)

opensuse

SUSE3 product(s)

linux enterprise desktoplinux enterprise serverlinux enterprise software development kit

Source: NVD CPE · 18 total CPE entries

Exploit & PoC Resources

POC AVAILABLEProof-of-concept code exists

Offensive Security exploit database

GitHub PoC Search

Community PoC repositories

Rapid7 / Metasploit

Metasploit module search

Security advisories & exploits

Official NIST entry

CVE Program entry

External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttp://git.savannah.gnu.org/cgit/inetutils.git/commit/?id=665f1e73cdd9b38e2d2e11b8db9958a315935592

PATCHhttp://security.freebsd.org/patches/SA-11:08/telnetd.patch

PATCHhttp://web.mit.edu/kerberos/www/advisories/MITKRB5-SA-2011-008.txt

PATCHhttp://git.savannah.gnu.org/cgit/inetutils.git/commit/?id=665f1e73cdd9b38e2d2e11b8db9958a315935592

PATCHhttp://security.freebsd.org/patches/SA-11:08/telnetd.patch

PATCHhttp://web.mit.edu/kerberos/www/advisories/MITKRB5-SA-2011-008.txt

ADVISORYhttp://lists.fedoraproject.org/pipermail/package-announce/2012-January/071627.html

ADVISORYhttp://lists.fedoraproject.org/pipermail/package-announce/2012-January/071640.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006117.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006118.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006119.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006120.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00002.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00004.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00005.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00007.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00010.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00011.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00014.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00015.html

ADVISORYhttp://secunia.com/advisories/46239

ADVISORYhttp://secunia.com/advisories/47341

ADVISORYhttp://secunia.com/advisories/47348

ADVISORYhttp://secunia.com/advisories/47357

ADVISORYhttp://secunia.com/advisories/47359

ADVISORYhttp://secunia.com/advisories/47373

ADVISORYhttp://secunia.com/advisories/47374

ADVISORYhttp://secunia.com/advisories/47397

ADVISORYhttp://secunia.com/advisories/47399

ADVISORYhttp://secunia.com/advisories/47441

ADVISORYhttp://security.freebsd.org/advisories/FreeBSD-SA-11:08.telnetd.asc

ADVISORYhttp://www.debian.org/security/2011/dsa-2372

ADVISORYhttp://www.debian.org/security/2011/dsa-2373

ADVISORYhttp://www.debian.org/security/2011/dsa-2375

ADVISORYhttp://www.exploit-db.com/exploits/18280/

ADVISORYhttp://www.mandriva.com/security/advisories?name=MDVSA-2011:195

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1851.html

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1852.html

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1853.html

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1854.html

ADVISORYhttp://www.securitytracker.com/id?1026460

ADVISORYhttp://www.securitytracker.com/id?1026463

ADVISORYhttps://exchange.xforce.ibmcloud.com/vulnerabilities/71970

ADVISORYhttp://lists.fedoraproject.org/pipermail/package-announce/2012-January/071627.html

ADVISORYhttp://lists.fedoraproject.org/pipermail/package-announce/2012-January/071640.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006117.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006118.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006119.html

ADVISORYhttp://lists.freebsd.org/pipermail/freebsd-security/2011-December/006120.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00002.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00004.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00005.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00007.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00010.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00011.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00014.html

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2012-01/msg00015.html

ADVISORYhttp://secunia.com/advisories/46239

ADVISORYhttp://secunia.com/advisories/47341

ADVISORYhttp://secunia.com/advisories/47348

ADVISORYhttp://secunia.com/advisories/47357

ADVISORYhttp://secunia.com/advisories/47359

ADVISORYhttp://secunia.com/advisories/47373

ADVISORYhttp://secunia.com/advisories/47374

ADVISORYhttp://secunia.com/advisories/47397

ADVISORYhttp://secunia.com/advisories/47399

ADVISORYhttp://secunia.com/advisories/47441

ADVISORYhttp://security.freebsd.org/advisories/FreeBSD-SA-11:08.telnetd.asc

ADVISORYhttp://www.debian.org/security/2011/dsa-2372

ADVISORYhttp://www.debian.org/security/2011/dsa-2373

ADVISORYhttp://www.debian.org/security/2011/dsa-2375

ADVISORYhttp://www.exploit-db.com/exploits/18280/

ADVISORYhttp://www.mandriva.com/security/advisories?name=MDVSA-2011:195

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1851.html

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1852.html

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1853.html

ADVISORYhttp://www.redhat.com/support/errata/RHSA-2011-1854.html

ADVISORYhttp://www.securitytracker.com/id?1026460

ADVISORYhttp://www.securitytracker.com/id?1026463

ADVISORYhttps://exchange.xforce.ibmcloud.com/vulnerabilities/71970

All References (84)

→

http://archives.neohapsis.com/archives/bugtraq/2011-12/0172.htmlBroken Link

→

http://git.savannah.gnu.org/cgit/inetutils.git/commit/?id=665f1e73cdd9b38e2d2e11b8db9958a315935592Patch · Third Party Advisory

→

http://lists.fedoraproject.org/pipermail/package-announce/2012-January/071627.htmlThird Party Advisory

→

http://lists.fedoraproject.org/pipermail/package-announce/2012-January/071640.htmlThird Party Advisory

→

http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006117.htmlVendor Advisory

→

http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006118.htmlVendor Advisory

→

http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006119.htmlVendor Advisory

→

http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006120.htmlVendor Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00002.htmlMailing List · Third Party Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00004.htmlMailing List · Third Party Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00005.htmlMailing List · Third Party Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00007.htmlMailing List · Third Party Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00010.htmlMailing List · Third Party Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00011.htmlMailing List · Third Party Advisory

→

http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00014.htmlMailing List · Third Party Advisory

Quick Facts

CVE IDCVE-2011-4862

CVSS Score10.0 / 10

SeverityCRITICAL

WeaknessCWE-120

CISA KEVNo

ExploitPOC

Affected8 vendor(s)

PublishedDec 25, 2011

Related CVEs (CWE-120)

Recommended Actions

→Apply vendor patches immediately
→Monitor CVE-2011-4862 in threat intel feeds
→Review IDS/IPS signatures for exploitation attempts

Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.

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