CVE-2026-4177

Multiple security issues have been discovered in the perl YAML::Syck module. A heap overflow occurs when class names exceed the initial 512-byte allocation, a base64 decoder could read past the buffer end on trailing newlines. strtok mutated n->type_id in place, corrupting shared node data, and 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.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.