A memory-safety vulnerability in Open Babel's MOL2 file format parser caused a NULL pointer dereference when reading a crafted input file.
The flaw was in OBAtom::SetFormalCharge as called from the MOL2
parser. A malformed atom record caused the parser to call the method
on a NULL atom pointer.
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 MOL2 file with the obabel
tool, the OBConversion API, or any of the language bindings (Python,
Ruby, Java, R, Perl, C#, PHP).
All releases up to and including 3.1.1.
3.2.0 (released 2026-05-26).
Fix commit: https://github.com/openbabel/openbabel/commit/e23a224b Tracked in #2862.
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.
Reported by Vedant Madane (@VedantMadane) via VulDB.
3.2.0Exploitability
AV:NAC:LAT:NPR:NUI:PVulnerable System
VC:NVI:NVA:LSubsequent System
SC:NSI:NSA:N2.1/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P