FreeBSD 'telnetd' Daemon Remote Buffer Overflow

critical Nessus Plugin ID 57462
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Synopsis

The telnet server has a remote buffer overflow vulnerability.

Description

A buffer overflow exists 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, and Heimdal 1.5.1 and earlier. The vulnerability also affects any 'telnetd' service derived from the FreeBSD codebase.
Successful exploitation could allow a remote attacker to execute arbitrary code via a long encryption key.

Note that this vulnerability has been exploited in the wild since December 2011.

Solution

Upgrade to the version of FreeBSD 'telnetd' specified in the vendor's advisory.

See Also

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

Plugin Details

Severity: Critical

ID: 57462

File Name: telnetd_encrypt_overflow.nbin

Version: 1.56

Type: remote

Published: 1/9/2012

Updated: 4/20/2021

Dependencies: find_service1.nasl, telnet.nasl

Risk Information

VPR

Risk Factor: High

Score: 8.9

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.3

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

Temporal Vector: E:F/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/o:freebsd:freebsd

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 12/23/2011

Vulnerability Publication Date: 12/23/2011

Exploitable With

Core Impact

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

ExploitHub (EH-11-760)

Reference Information

CVE: CVE-2011-4862

BID: 51182

DSA: 2372, 2373, 2375

FreeBSD: SA-11:08.telnetd

RHSA: 2011:1851, 2011:1852