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High ALAS2-2026-3216 1 CVE

Important: perl-YAML-Syck security update (Amazon Linux 2)

Published Mar 30, 2026 · Updated Apr 1, 2026

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2026-4177: 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.

Fixed packages 2

ReleasePackageFixed in
Amazon Linux · 2 perl-YAML-Syck 0:1.27-3.amzn2.0.4
Amazon Linux · 2 perl-YAML-Syck-debuginfo 0:1.27-3.amzn2.0.4

Vulnerabilities 1

  • Critical 9.1

    YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter

    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 c…

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-4177.html