Buffer Overflow Affecting perl-YAML-Syck-tests package, versions <0:1.37-1.amzn2023.0.1


Severity

Recommended
0.0
high
0
10

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.45% (39th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-AMZN2023-PERLYAMLSYCKTESTS-15922172
  • published7 Apr 2026
  • disclosed16 Mar 2026

Introduced: 16 Mar 2026

CVE-2026-4177  (opens in a new tab)
CWE-120  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 perl-YAML-Syck-tests to version 0:1.37-1.amzn2023.0.1 or higher.
This issue was patched in ALAS2023-2026-1517.

NVD Description

Note: Versions mentioned in the description apply only to the upstream perl-YAML-Syck-tests package and not the perl-YAML-Syck-tests package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

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 Base Scores

version 3.1