GHSA-mjmg-352j-f456 Open Babel has out-of-bounds write in MOPAC IN translationVectors[] (Tv atom)

• PyPI openbabel: < 3.2.0 → fixed in 3.2.0

Summary A memory-safety vulnerability in Open Babel's MOPAC input parser allowed an out-of-bounds write into the `translationVectors[]` array when reading Tv (translation-vector) atoms from a crafted input file. Details The MOPAC IN reader stored Tv-atom translation vectors into a fixed-size `translationVectors[]` array. A malformed input with more than three Tv atoms (or three plus extras) could push more vectors than the array had slots, causing a write past the end of the array. One of five `translationVectors[]` OOB writes in the TALOS 2022 batch. Impact Open Babel is a C++ library and CLI used to read and write chemistry file formats; it is shipped by Linux distributions and embedded in services that may parse untrusted input. Triggering this vulnerability requires the victim to open a malicious MOPAC input file with the `obabel` tool, the `OBConversion` API, or any of the language bindings (Python, Ruby, Java, R, Perl, C#, PHP). Affected versions All releases up to and including 3.1.1. Patched version 3.2.0 (released 2026-05-26). Patch Fix commit: https://github.com/openbabel/openbabel/commit/40e85213 A minimized reproducer for this CVE is checked in under `test/files/fuzz_regress/` and is exercised on every CI build under ASAN+UBSAN by the `fuzzregresstest` harness. Credit Reported by Cisco TALOS.