TELNET: NEW-ENVIRON Overflow

This signature detects attempts to exploit a known vulnerability in telnet clients. The env_opt_add function of some telnet clients incorrectly handles NEWENVIRON sub-options. Attackers can send a maliciously crafted SEND command to a telnet client to overflow the buffer, then execute arbitrary code on the target system with the telnet client account privileges.

Extended Description

Multiple vendors' Telnet client applications are reported prone to a remote buffer-overflow vulnerability. This vulnerability reportedly occurs in the 'env_opt_add()' function in the 'telnet.c' source file, which is apparently common source for all the affected vendors. A remote attacker may exploit this vulnerability to execute arbitrary code on some of the affected platforms in the context of a user that is using the vulnerable Telnet client to connect to a malicious server.

Affected Products

F5 3-dns,Freebsd freebsd

References

BugTraq: 12919

CVE: CVE-2005-0468

URL: http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2005-001-telnet.txt http://www.idefense.com/application/poi/display?id=221&type=vulnerabilities

Short Name

TELNET:OVERFLOW:NEW-ENVIRON-OF

Severity

Major

Recommended

False

Recommended Action

Drop

TELNET: NEW-ENVIRON Overflow

Extended Description

Affected Products

References

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