GNU Bison improperly handles grammar‑defined output paths. Grammar directives such as %output and %header allow specifying file paths, which are accepted without restriction and override caller‑suppl…
Summary
GNU Bison improperly handles grammar‑defined output paths. Grammar directives such as %output and %header allow specifying file paths, which are accepted without restriction and override caller‑supplied output options. When processing attacker-supplied grammar, this behavior allows directing generated files to arbitrary writable locations on the filesystem, potentially overwriting existing files accessible to the Bison process. Maintainers of this project were notified about this vulnerabilit…
In-depth triage · Auto channel
No in-depth report has been generated yet (DR-003 v2 AI pipeline is under construction).
Lint boundary warnings (3)
The following non-blocking warnings were raised during the lint phase of this triage (e.g. reference URLs not yet on the allowlist). They do not affect entry usability and are disclosed for transparency (see DR-002).
-
REF_URL_NOT_ALLOWLISTEDurl not in allowlist: https://cert.pl/en/posts/2026/07/CVE-2026-56389 -
REF_URL_NOT_ALLOWLISTEDurl not in allowlist: https://cgit.git.savannah.gnu.org/cgit/bison.git/ -
REF_URL_NOT_ALLOWLISTEDurl not in allowlist: https://cgit.git.savannah.gnu.org/cgit/bison.git/commit/?id=8d101c19d4d9aaedf83a448c925513742d4efcf0
Sources
- NVD DATABASE
Original Links
- https://cert.pl/en/posts/2026/07/CVE-2026-56389
- https://cgit.git.savannah.gnu.org/cgit/bison.git/
- https://cgit.git.savannah.gnu.org/cgit/bison.git/commit/?id=8d101c19d4d9aaedf83a448c925513742d4efcf0
Timeline
- nvd_ingest NVD