CVE-2026-8376
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
Perl versions up to 5.43.10 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds. The bug in Perl_study_chunk leads to an undersized buffer allocation and subsequent out-of-bounds write.
Risk Assessment
High risk – an attacker can supply a crafted regular expression causing a buffer overflow, potentially leading to arbitrary code execution in the Perl process.
Recommendation
Update Perl to version 5.43.11 or later, which contains the fix.
Original NVD description (English source)
Perl versions through 5.43.10 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds. Perl_study_chunk in regcomp_study.c checked the size of the joined substring buffer in characters rather than bytes. For a quantified fixed substring with a large minimum count, the byte length mincount * l could overflow SSize_t, producing an undersized SvGROW allocation; the subsequent copy writes past the end of the buffer. A caller that compiles an attacker-controlled regular expression on a 32-bit perl build triggers a heap buffer overflow at compile time.