High CVSS 7.5

Overview

Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an SSH2 packet with a base argument that is larger than the mod argument, which causes the modpow function to write memory before the beginning of its buffer, and (2) remote malicious servers to cause a denial of service (client crash) and possibly execute arbitrary code via a large bignum during authentication.

Risk analysis

This vulnerability is rated 🟠 HIGH.

  • CVSS: 7.5 (HIGH)
  • Detected tags: none (tag impact: LOW)

Recommended actions:

  • Prioritize remediation based on business criticality and exposure.
  • Limit exposure and increase monitoring until fixed.

Recommended tools

Tags