CVE-2011-4862

High PUBLISHED

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...

FreeBSD · FreeBSD

Not yet in CISA KEV

PoC available

Recommended Action

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

View KEV Feed Talk to Sales

Confidence

High

Exploitation Status

PoC available

Observed in Sensors

Attempts (30d)

—

Unique Attacker IPs

—

CISA KEV

Not yet in CISA KEV

CVSS / EPSS

10.0 High

At a Glance

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.

metasploit

CVE Published: Dec 25, 2011
Exploitation Reported: Dec 25, 2011
CVSS: 10.0 High
EPSS: —

Remote Low complexity Unauthenticated

Affected Versions

Vendor	Product	Version	Status
n/a	n/a	n/a	Affected

CVE References

SUSE-SU-2012:0042 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00010...
DSA-2375 debian.org · Vendor Advisory http://www.debian.org/security/2011/dsa-2375
RHSA-2011:1854 redhat.com · Vendor Advisory http://www.redhat.com/support/errata/RHSA-2011-1854.html
SUSE-SU-2012:0018 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00004...
DSA-2372 debian.org · Vendor Advisory http://www.debian.org/security/2011/dsa-2372

Show 37 more references

FEDORA-2011-17493 lists.fedoraproject.org · Vendor Advisory http://lists.fedoraproject.org/pipermail/package-announce/2012-Januar...
FreeBSD-SA-11:08 security.freebsd.org · Vendor Advisory http://security.freebsd.org/advisories/FreeBSD-SA-11:08.telnetd.asc
openSUSE-SU-2012:0019 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00005...
FEDORA-2011-17492 lists.fedoraproject.org · Vendor Advisory http://lists.fedoraproject.org/pipermail/package-announce/2012-Januar...
MDVSA-2011:195 mandriva.com · Vendor Advisory http://www.mandriva.com/security/advisories?name=MDVSA-2011:195
SUSE-SU-2012:0024 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00007...
SUSE-SU-2012:0050 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00011...
RHSA-2011:1852 redhat.com · Vendor Advisory http://www.redhat.com/support/errata/RHSA-2011-1852.html
RHSA-2011:1853 redhat.com · Vendor Advisory http://www.redhat.com/support/errata/RHSA-2011-1853.html
openSUSE-SU-2012:0051 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00014...
SUSE-SU-2012:0010 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00002...
SUSE-SU-2012:0056 lists.opensuse.org · Vendor Advisory http://lists.opensuse.org/opensuse-security-announce/2012-01/msg00015...
RHSA-2011:1851 redhat.com · Vendor Advisory http://www.redhat.com/support/errata/RHSA-2011-1851.html
DSA-2373 debian.org · Vendor Advisory http://www.debian.org/security/2011/dsa-2373
47399 secunia.com · Third-Party Advisory http://secunia.com/advisories/47399
47359 secunia.com · Third-Party Advisory http://secunia.com/advisories/47359
47374 secunia.com · Third-Party Advisory http://secunia.com/advisories/47374
47341 secunia.com · Third-Party Advisory http://secunia.com/advisories/47341
47357 secunia.com · Third-Party Advisory http://secunia.com/advisories/47357
46239 secunia.com · Third-Party Advisory http://secunia.com/advisories/46239
47397 secunia.com · Third-Party Advisory http://secunia.com/advisories/47397
47373 secunia.com · Third-Party Advisory http://secunia.com/advisories/47373
47441 secunia.com · Third-Party Advisory http://secunia.com/advisories/47441
47348 secunia.com · Third-Party Advisory http://secunia.com/advisories/47348
18280 exploit-db.com · Exploit http://www.exploit-db.com/exploits/18280/
78020 osvdb.org · VDB Entry http://osvdb.org/78020
1026463 securitytracker.com · VDB Entry http://www.securitytracker.com/id?1026463
1026460 securitytracker.com · VDB Entry http://www.securitytracker.com/id?1026460
multiple-telnetd-bo(71970) exchange.xforce.ibmcloud.com · VDB Entry https://exchange.xforce.ibmcloud.com/vulnerabilities/71970
20111226 MITKRB5-SA-2011-008 buffer overflow in telnetd [CVE-2011-4862] archives.neohapsis.com · Mailing List http://archives.neohapsis.com/archives/bugtraq/2011-12/0172.html
[freebsd-security] 20111223 Merry Christmas from the FreeBSD Security Team lists.freebsd.org · Mailing List http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006...
[freebsd-security] 20111223 Merry Christmas from the FreeBSD Security Team lists.freebsd.org · Mailing List http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006...
[freebsd-security] 20111223 Merry Christmas from the FreeBSD Security Team lists.freebsd.org · Mailing List http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006...
[freebsd-security] 20111223 Merry Christmas from the FreeBSD Security Team lists.freebsd.org · Mailing List http://lists.freebsd.org/pipermail/freebsd-security/2011-December/006...
security.freebsd.org/patches/SA-11:08/telnetd.patch security.freebsd.org · CVE Record http://security.freebsd.org/patches/SA-11:08/telnetd.patch
git.savannah.gnu.org/cgit/inetutils.git/commit git.savannah.gnu.org · CVE Record http://git.savannah.gnu.org/cgit/inetutils.git/commit/?id=665f1e73cdd...
web.mit.edu/kerberos/www/advisories/MITKRB5-SA-2011-008.txt web.mit.edu · CVE Record http://web.mit.edu/kerberos/www/advisories/MITKRB5-SA-2011-008.txt

Recommended Actions

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.

Known Exploited Vulnerability Sources

Catalogues that list this CVE as a known exploited vulnerability.

Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.

Learn about Pro API access

Source	Added
CVE First	2011-12-25 01:00 UTC

Scanner Artifacts

Nuclei and Metasploit references linked to this CVE.

Scanner	Reference	Detected
Metasploit	https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/telnet/telnet_encrypt_keyid.rb	Apr 29, 2025

CVSS Scores

CVSS v2.0 10.0 High

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

Exploitation Status

Proof of concept available

Recorded 2017-02-02 18:12:56 UTC · GitHub

Scanner Integrations

Scanner	Reference	Detected
Metasploit	https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/telnet/telnet_encrypt_keyid.rb	Apr 29, 2025

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

kpawar2410/CVE-2011-4862

github · Created 2020-02-06 09:30:45 UTC · 1 stars

Final Project for Security and Privacy CS 600.443

hdbreaker/GO-CVE-2011-4862

github · Created 2017-02-02 18:12:56 UTC · 4 stars

Go Exploit for CVE-2011-4862

telnet_encrypt_keyid

metasploit · Created Unknown

Metasploit module for CVE-2011-4862

telnet_encrypt_keyid

metasploit · Created Unknown

Metasploit module for CVE-2011-4862

Automate This Intelligence with the Pro API

Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

View Pro Pricing View API Docs

Pro API Example

GET /api/v2/pro/kevs/CVE-2011-4862

{
  "cve_id": "CVE-2011-4862",
  "title": "Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0,...",
  "affected_vendor": "FreeBSD",
  "affected_product": "FreeBSD",
  "affected_versions": [
    { "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
  ],
  "confidence": "High",
  "cvss_score": 10.0,
  "epss_score": null,
  "exploit_status": {
    "exploited_in_the_wild": false,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "...": "Pro API fields" },
  "proof_of_concepts": [ "..." ],
  "scanner_integrations": [ "..." ]
}

The free JSON API returns basic KEV fields only. Confidence, telemetry, and artifact enrichment require Pro API access.

CVE-2011-4862

At a Glance

Affected Versions

CVE References

Recommended Actions

Known Exploited Vulnerability Sources

Scanner Artifacts

Virtual Patch

CVSS Scores

Exploitation Status

Scanner Integrations

Potential Proof of Concepts

Timeline

Automate This Intelligence with the Pro API