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Medium ALAS2023-2026-1769 1 CVE

Moderate: perl-YAML-Syck security update (Amazon Linux 2023)

Published May 25, 2026 · Updated May 25, 2026

Summary

Package updates are available for Amazon Linux 2023 that fix the following vulnerabilities: CVE-2026-5089: 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.

Fixed packages 4

ReleasePackageFixed in
Amazon Linux · 2023 perl-YAML-Syck 0:1.37-1.amzn2023.0.3
Amazon Linux · 2023 perl-YAML-Syck-debuginfo 0:1.37-1.amzn2023.0.3
Amazon Linux · 2023 perl-YAML-Syck-debugsource 0:1.37-1.amzn2023.0.3
Amazon Linux · 2023 perl-YAML-Syck-tests 0:1.37-1.amzn2023.0.3

Vulnerabilities 1

  • High 7.3

    YAML::Syck versions before 1.38 for Perl has an out-of-bounds read

    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 (…

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-5089.html