Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack.
S_measure_struct adds each item's size times its repeat count to a running total with no overflow check, so a large repeat count in a pack or unpack template wraps the signed SSize_t total negative. The @, X, and x position codes then guard their moves with a signed length comparison that passes when the length is negative, advancing the buffer pointer out of bounds.
A template derived from untrusted input can read heap memory past the buffer and return it to the caller.
References
| Link | Resource |
|---|---|
| https://github.com/Perl/perl5/commit/40754edc72dd3e513d758153c0e2f0215897740e.patch | Patch |
| https://github.com/Perl/perl5/commit/5f7eb6bbbe0510964e3fb1d6bb691e5445913e55.patch | Patch |
| http://www.openwall.com/lists/oss-security/2026/07/13/6 | Mailing List Patch Third Party Advisory |
Configurations
History
No history.
Information
Published : 2026-07-13 17:17
Updated : 2026-09-08 22:18
NVD link : CVE-2026-57432
Mitre link : CVE-2026-57432
CVE.ORG link : CVE-2026-57432
JSON object : View
Products Affected
perl
- perl
