Insufficient verification of data authenticity in PuTTY - CVE-2021-36367

 

Insufficient verification of data authenticity in PuTTY - CVE-2021-36367

Published: July 20, 2021


Vulnerability identifier: #VU55005
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2021-36367
CWE-ID: CWE-345
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: Simon Tatham
Affected software:
PuTTY

Detailed vulnerability description

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to insufficient verification of data source when processing authentication responses. A remote attacker can send a spoofed authentication prompt even after an SSH session has been established with the original server and trick the victim into providing authentication credentials.


How to mitigate CVE-2021-36367

Install updates from vendor's website.

Sources