MEDIUM 4.0 Microsoft
CVE-2026-13221
Perl versions through 5.43.9 produce silently incorrect regular expression matches when an alternation of more than 65535 fixed string branches is compiled into a trie in Perl_study_chunk
Microsoft Security Update 2026-Jul: Perl versions through 5.43.9 produce silently incorrect regular expression matches when an alternation of more than 65535 fixed string branches is compiled into a trie in Perl_study_chunk
Affected Products
- azl3 perl 5.38.2-512 on Azure Linux 3.0
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-13221
- https://nvd.nist.gov/vuln/detail/CVE-2026-13221
This medium severity vulnerability with a CVSS score of 4.0 was published on 2026-07-14 via Microsoft. Affected: azl3 perl 5.38.2-512 on Azure Linux 3.0.
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