OpenSSH < 2.3.2 SSHv2 Public Key Authentication Bypass

Critical Nessus Network Monitor Plugin ID 1985

Synopsis

The remote host is vulnerable to a flaw that allows for the bypassing of authentication.

Description

The remote host is running OpenSSH 2.3.1. This version is vulnerable to a flaw that allows any attacker who can obtain the public key of a valid SSH user to log into this host without any authentication.

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.

Solution

Upgrade to OpenSSH 2.3.2 or higher.

See Also

http://www.openbsd.org/advisories/ssh_bypass.txt

Plugin Details

Severity: Critical

ID: 1985

File Name: 1985.prm

Family: SSH

Published: 2004/08/20

Modified: 2016/11/23

Dependencies: 1997, 3059

Nessus ID: 10608

Risk Information

Risk Factor: Critical

CVSSv2

Base Score: 10

Temporal Score: 8.7

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

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

CVSSv3

Base Score: 9.8

Temporal Score: 9.4

Vector: CVSS3#AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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

Vulnerability Information

CPE: cpe:/a:openbsd:openssh

Reference Information

CVE: CVE-2001-1585

BID: 2356

OSVDB: 504