CVE-2026-49420 (High) detected in src4.0.4

[mend-bolt-for-github]

CVE-2026-49420 - High Severity Vulnerability

Vulnerable Library - src4.0.4

Library home page: https://github.com/MidnightBSD/src.git

Found in base branches: stable/4.0, master

Vulnerable Source Files (1)

/sys/netinet/libalias/alias_smedia.c

Vulnerability Details

The RTSP handler in libalias rewrote outgoing packets into a fixed-length stack buffer without checking whether the rewritten data fit in the buffer, or whether the result fit back in the original packet.
A host sending crafted RTSP traffic from inside a NAT gateway using libalias can overflow a stack buffer, potentially achieving remote code execution in the kernel (when using ipfw(4) NAT) or in the natd(8) process (which generally runs as the root user).

Publish Date: 2026-08-19

URL: CVE-2026-49420

CVSS 3 Score Details (8.8)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Adjacent
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: High
  • Integrity Impact: High
  • Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Release Date: 2026-08-19

Fix Resolution: https://github.com/freebsd/freebsd-src.git - release/14.3.0-p16,https://github.com/freebsd/freebsd-src.git - release/14.4.0-p7,https://github.com/freebsd/freebsd-src.git - release/15.1.0-p1,https://github.com/freebsd/freebsd-src.git - release/15.0.0-p11

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