CVE-2025-10995: Open Babel out-of-bounds write in zipstream decompression

CVE-2025-10995 · Severity: high · CVSS 7.8 · Published 2026-06-30

Open Babel, a widely used library for processing chemistry file formats, contains a memory-safety vulnerability in its decompression component. An attacker could provide a specially crafted gzip-compressed chemistry file that, when opened by a user or processed by a service, could lead to a system crash or unauthorized code execution. This affects researchers and organizations using the library's command-line tools or its various programming language interfaces (such as Python, Java, and C#).

Technologies: openbabel (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2025-10995 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-10995 being exploited in the wild.
How severe is CVE-2025-10995?
High severity, with a CVSS score of 7.8, published 30 June 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-2025-10995?
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-2025-10995 attacked?
It is attacked with local access, in a software library.
Am I affected by CVE-2025-10995?
Check whether you run 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 write vulnerability exists in Open Babel's bundled zipstream implementation, specifically within the 'basic_unzip_streambuf::underflow' function in 'src/zipstreamimpl.h'. The flaw is caused by the use of 'memcpy' on overlapping memory regions during the decompression buffer refill path, which constitutes undefined behavior and results in memory corruption. An attacker can exploit this by providing a malicious gzip-compressed chemistry file to be parsed via the 'obabel' CLI, 'OBConversion' API, or any supported language bindings. The vulnerability was identified via OSS-Fuzz and is addressed in version 3.2.0.

Affected products

  • Open Babel Open Babel <= 3.1.1

Identifiers

  • CVE-2025-10995
  • GHSA-8j3x-m868-cpw8
  • PYSEC-2026-2776

Timeline

  • 2025-09-14: other: Initial bug report submitted
  • 2026-05-26: patched: Version 3.2.0 released
  • 2026-06-30: advisory: GitHub Advisory published

References

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