CVE-2026-19082
Medium
Elevated severity or exploit probability.
Description
Imager versions from 0.45_02 before 1.034 for Perl may expose adjacent heap bytes via strlen() over-read from zero-count ASCII EXIF entries in copy_string_tags. copy_string_tags() computes an ASCII EXIF tag's length as `entry->size - 1` to strip the trailing NUL. A zero-count ASCII entry sets `entry->size` to 0, and the derived length reaches i_tags_add() as -1, which is interpreted as a request to call strlen(), scanning past the entry to the next NUL and copying those bytes into the tag. JPEG reaches this path via im_decode_exif(), as does the separate Imager::File::WEBP distribution, which is fixed by upgrading Imager. Any caller of Imager->read() on an attacker-supplied image with such an entry may receive an exif_* tag holding adjacent heap bytes instead of an empty string.
References
- https://github.com/tonycoz/imager/commit/24bde0427a113264d53f45a9c29ae756d84c82fe.patch
- https://github.com/tonycoz/imager/security/advisories/GHSA-hx46-55wp-hv6m
- https://metacpan.org/release/TONYC/Imager-1.034/changes
- http://www.openwall.com/lists/oss-security/2026/08/07/6
- https://github.com/tonycoz/imager/security/advisories/GHSA-hx46-55wp-hv6m