SB2023122224 - Gentoo update for libssh



SB2023122224 - Gentoo update for libssh

Published: December 22, 2023

Security Bulletin ID SB2023122224
Severity
High
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 67% Medium 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Buffer overflow (CVE-ID: CVE-2021-3634)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when handling shared secrets. A remote attacker can supply a shared secret of a different size, trigger a memory corruption during the second key re-exchange and crash the application or potentially execute arbitrary code.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.


2) Input validation error (CVE-ID: CVE-2023-1667)

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to multiple errors in kex implementation, related to kex guessing algorithm. A remote attacker can bypass implemented security restrictions.


3) Improper Authentication (CVE-ID: CVE-2023-2283)

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error within the pki_verify_data_signature() function in pki_crypto.c. The pki_key_check_hash_compatible() function can return SSH_OK value if memory allocation error happens later in the function. The  A remote attacker can bypass authentication process and gain unauthorized access to the system.


Remediation

Install update from vendor's website.