High CVSS 7.8

Overview

The HMAC implementation (crypto/hmac.c) in the Linux kernel before 4.14.8 does not validate that the underlying cryptographic hash algorithm is unkeyed, allowing a local attacker able to use the AF_ALG-based hash interface (CONFIG_CRYPTO_USER_API_HASH) and the SHA-3 hash algorithm (CONFIG_CRYPTO_SHA3) to cause a kernel stack buffer overflow by executing a crafted sequence of system calls that encounter a missing SHA-3 initialization.

Risk analysis

This vulnerability is rated 🟠 HIGH.

  • CVSS: 7.8 (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