Vulnerability 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.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Toddr | Yaml\ | < 1.37, \ |
Related Weaknesses (CWE)
References
- https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4Patch
- https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21Release Notes
- http://www.openwall.com/lists/oss-security/2026/03/16/6Mailing ListThird Party Advisory
FAQ
What is CVE-2026-4177?
CVE-2026-4177 is a vulnerability with a CVSS score of 9.1 (CRITICAL). 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 ...
How severe is CVE-2026-4177?
CVE-2026-4177 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-4177?
Check the references section above for vendor advisories and patch information. Affected products include: Toddr Yaml\.