Poppler is a PDF rendering library. Versions prior to 25.06.0 use std::atomic_int for reference counting. Because std::atomic_int is only 32 bits, it is possible to overflow the reference count and trigger a use-after-free. Version 25.06.0 patches the issue.
References
- http://www.openwall.com/lists/oss-security/2025/07/11/5
- http://www.openwall.com/lists/oss-security/2025/07/12/1
- https://gitlab.freedesktop.org/poppler/poppler/-/commit/04bd91684ed41d67ae0f10cde0660e4ed74ac203
- https://gitlab.freedesktop.org/poppler/poppler/-/commit/ac36affcc8486de38e8905a8d6547a3464ff46e5
- https://gitlab.freedesktop.org/poppler/poppler/-/issues/1581
- https://gitlab.freedesktop.org/poppler/poppler/-/merge_requests/1828
- https://securitylab.github.com/advisories/GHSL-2025-054_poppler/