Amazon Linux 2 Security Advisory: ALAS2-2026-3216
Advisory Released Date: 2026-04-01
Advisory Updated Date: 2026-04-01
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. (CVE-2026-4177)
Affected Packages:
perl-YAML-Syck
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update perl-YAML-Syck or yum update --advisory ALAS2-2026-3216 to update your system.
aarch64:
perl-YAML-Syck-1.27-3.amzn2.0.4.aarch64
perl-YAML-Syck-debuginfo-1.27-3.amzn2.0.4.aarch64
i686:
perl-YAML-Syck-1.27-3.amzn2.0.4.i686
perl-YAML-Syck-debuginfo-1.27-3.amzn2.0.4.i686
src:
perl-YAML-Syck-1.27-3.amzn2.0.4.src
x86_64:
perl-YAML-Syck-1.27-3.amzn2.0.4.x86_64
perl-YAML-Syck-debuginfo-1.27-3.amzn2.0.4.x86_64