Denial of service in OpenSSH - CVE-2016-8858

 

Denial of service in OpenSSH - CVE-2016-8858

Published: October 21, 2016 / Updated: December 19, 2016


Vulnerability identifier: #VU1033
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2016-8858
CWE-ID: CWE-401
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: OpenSSH
Affected software:
OpenSSH

Detailed vulnerability description

The vulnerability allows a remote unauthenticated attacker to cause DoS conditions on the target system.

The weakness is due to flaw in kex_input_kexinit() function. By sending a specially crafted data during the key exchange process, attackers can cause memory exhaustion. Consuming up to 128 MB per connection may lead to denial of service.

Successful exploitation of the vulnerability results in denial of service of the vulnerable system.

How to mitigate CVE-2016-8858

Install the latest OpenSSH version 7.4.

Sources