CVE-2026-2704: Open Babel out-of-bounds read in CIF File Handler

CVE-2026-2704 · Severity: medium · CVSS 4.4 · Published 2026-02-19

Open Babel, a widely used library for processing chemical data, contains a flaw in how it reads certain chemistry file formats (CIF). An attacker could create a specially crafted file that, when opened by a user or processed by a service, causes the application to crash or potentially leak small amounts of memory. This could disrupt scientific workflows or affect services that automatically process chemical data uploaded by users.

Technologies: Openbabel Open Babel, openbabel (PyPI). Vendors: Openbabel, PyPI.

Quick answers

Is CVE-2026-2704 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-2704 being exploited in the wild.
How severe is CVE-2026-2704?
Medium severity, with a CVSS score of 4.4, published 19 February 2026.
Which products and versions are affected?
openbabel (PyPI) < 3.2.0, ECOSYSTEM:introduced=0,fixed=3.2.0.
Is there a fix for CVE-2026-2704?
Yes. openbabel (PyPI): upgrade to 3.2.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-2704 attacked?
It is attacked with local access, in a software library.
Am I affected by CVE-2026-2704?
Check whether you run Openbabel Open Babel or openbabel (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • openbabel (PyPI): upgrade to 3.2.0 or later
    pip install "openbabel>=3.2.0"

Technical details

An out-of-bounds read vulnerability exists in Open Babel's CIF file format parser within the 'OpenBabel::transform3d::DescribeAsString' function. The root cause is a failure to properly validate the length of symmetry-operation strings, leading the parser to read past the end of an internal buffer during description formatting. An attacker can exploit this by providing a malformed CIF file to the 'obabel' CLI tool, the OBConversion API, or associated language bindings. Successful exploitation requires user interaction (opening the file) and can result in a denial-of-service (crash) or limited information disclosure. The issue is addressed in version 3.2.0.

Affected products

  • Open Babel openbabel <= 3.1.1

Identifiers

  • CVE-2026-2704
  • GHSA-6xw4-2g22-26h8
  • PYSEC-2026-2774

Timeline

  • 2026-05-26: patched: Version 3.2.0 released
  • 2026-06-30: disclosed: GitHub Advisory published

References

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