VULNERABILITY INTELLIGENCE

CVE-2026-4177

CVSS score9.1 CRITICAL
EPSS probability0.45%
CISA KEVNot currently listed
Published2026-03-16
Last modified2026-07-15
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Description

YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter. The heap overflow occurs when class names exceed the initial 512-byte allocation. The base64 decoder could read past the buffer end on trailing newlines. strtok mutated n->type_id in place, corrupting shared node data. A memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string 'a' was leaked on early return.

Weakness classification

  • 9b29abf9-4ab0-4765-b253-1875cd9b441e: CWE-122
  • 0b0ca135-0b70-47e7-9f44-1890c2a1c46c: CWE-120

Primary references