OpenSSH < 3.1 Channel Code Off by One Privilege Escalation

High Nessus Network Monitor Plugin ID 1990


The remote host is vulnerable to a buffer overflow.


The remote host is running a version of OpenSSH which is older than 3.1. Versions prior than 3.1 are vulnerable to an off by one error that allows local users to gain root access, and it may be possible for remote users to similarly compromise the daemon for remote access. In addition, a vulnerable SSH client may be compromised by connecting to a malicious SSH daemon that exploits this vulnerability in the client code, thus compromising the client system.

Note: PVS has solely relied on the banner of the SSH client to perform this check. Any backported patches or workarounds such as recompiling or edited configurations are not observable through the banner.


Upgrade to OpenSSH 3.1 or higher.

Plugin Details

Severity: High

ID: 1990

Family: SSH

Published: 2004/08/20

Modified: 2016/11/23

Dependencies: 1997, 3059

Nessus ID: 10883

Risk Information

Risk Factor: High


Base Score: 7.2

Temporal Score: 6

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:F/RL:OF/RC:C


Base Score: 8.4

Temporal Score: 7.8


Temporal Vector: CVSS3#E:F/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:openbsd:openssh

Exploitable With

Core Impact

Reference Information

CVE: CVE-2002-0083

BID: 4241