CVE-2026-15534 (GCVE-0-2026-15534)

Vulnerability from cvelistv5 – Published: 2026-08-09 17:49 – Updated: 2026-09-08 21:31
VLAI
Title
Perl versions through 5.45.1 have out-of-bounds heap reads and writes during regular expression matching via an undersized superlinear cache in S_regmatch
Summary
Perl versions through 5.45.1 have out-of-bounds heap reads and writes during regular expression matching via an undersized superlinear cache in S_regmatch. The regex engine's superlinear cache holds one bit per subject position for each participating WHILEM node, so the bit count is the subject length plus one times the number of nodes. Nothing checks that product for positive overflow of the signed 32-bit count: a 286331153 byte subject matched against a pattern with 15 participating nodes stores the count as 14, leaving a two byte cache. The cache is then indexed from the real match position and node number, so reads go past the end of the allocation, and on failure CACHEsayNO sets a bit past it. A caller that matches an attacker controlled subject of this size against a pattern of this shape can crash the process or corrupt heap memory.
Severity
5.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-12 17:38 UTC
CWE
Assigner
CPANSec CNA under the redhat root
CNA scorecard C 63/100 over 297 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Affected: 0 , ≤ 5.45.1 (custom)
Show details on NVD website
To clipboard 

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