Amazon Linux 2 Security Advisory: ALAS2-2026-3327
Advisory Released Date: 2026-06-08
Advisory Updated Date: 2026-06-08
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read.
The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer:
while ( colon >= ptr && *colon != ':' )
{
colon--;
}
if ( *colon == ':' ) *colon = '\0'; // colon may be ptr-1 here
When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer. (CVE-2026-5089)
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 ALAS2-2026-3327 to update your system.
aarch64:
perl-YAML-Syck-1.27-3.amzn2.0.5.aarch64
perl-YAML-Syck-debuginfo-1.27-3.amzn2.0.5.aarch64
i686:
perl-YAML-Syck-1.27-3.amzn2.0.5.i686
perl-YAML-Syck-debuginfo-1.27-3.amzn2.0.5.i686
src:
perl-YAML-Syck-1.27-3.amzn2.0.5.src
x86_64:
perl-YAML-Syck-1.27-3.amzn2.0.5.x86_64
perl-YAML-Syck-debuginfo-1.27-3.amzn2.0.5.x86_64