SSH Protocol Authentication Bypass (Remote Exploit Check)

critical Nessus Plugin ID 118154
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Synopsis

The remote server is vulnerable to an authentication bypass.

Description

The remote ssh server is vulnerable to an authentication bypass. An attacker can bypass authentication by presenting SSH2_MSG_USERAUTH_SUCCESS message in place of the SSH2_MSG_USERAUTH_REQUEST method that normally would initiate authentication.

Note: This vulnerability was disclosed in a libssh advisory but has also been observed as applicable to other applications and software packages.

Solution

Upgrade to libssh 0.7.6 / 0.8.4 or later, if applicable. Otherwise, contact your product vendor.

See Also

http://www.nessus.org/u?6f6b157e

http://www.nessus.org/u?505261f8

http://www.nessus.org/u?58a0f73d

Plugin Details

Severity: Critical

ID: 118154

File Name: libssh_0_8_4_remote.nasl

Version: 1.18

Type: remote

Family: Misc.

Published: 10/17/2018

Updated: 5/15/2020

Dependencies: find_service1.nasl

Risk Information

CVSS Score Source: CVE-2018-10933

VPR

Risk Factor: High

Score: 7.7

CVSS v2

Risk Factor: Medium

Base Score: 6.4

Temporal Score: 5

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

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

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 8.2

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: E:P/RL:O/RC:C

Vulnerability Information

Exploit Available: true

Exploit Ease: Exploits are available

Vulnerability Publication Date: 10/16/2018

Reference Information

CVE: CVE-2018-10933, CVE-2018-1000805

BID: 105677, 106762

IAVA: 2018-A-0347-S