Bug 2448277 (CVE-2026-4177)

Summary: CVE-2026-4177 perl-YAML-Syck: YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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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.
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Bug Depends On: 2448280, 2448281    
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Description OSIDB Bzimport 2026-03-16 23:02:07 UTC 
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.