Is CVE-2026-112915 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-112915 being exploited in the wild.

How severe is CVE-2026-112915?

Medium severity, with a CVSS score of 5.5, published 20 October 2026.

Which products and versions are affected?

filelock (PyPI) >= 3.20.4, <= 4.2.0, ECOSYSTEM:introduced=3.20.4,fixed=4.2.1; Tox-Dev Filelock 3.20.4 to 4.2.1.

Is there a fix for CVE-2026-112915?

Yes. filelock (PyPI): upgrade to 4.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-112915 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-112915?

Check whether you run filelock (PyPI) or Tox-Dev Filelock 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.

CVE-2026-112915: filelock ReadWriteLock unbounded SQLite query denial of service

Q: Is there a fix for CVE-2026-112915?

Yes. filelock (PyPI): upgrade to 4.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-112915 attacked?

It is attacked with local access, in a software library.

Q: Am I affected by CVE-2026-112915?

Check whether you run filelock (PyPI) or Tox-Dev Filelock 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.

CVE-2026-112915 · Severity: medium · CVSS 5.5 · Published 2026-10-20

filelock is a Python library that provides file locking across platforms. Versions 3.20.4 through 4.2.1 contain a denial-of-service vulnerability in the ReadWriteLock class, where a local attacker can craft a malicious SQLite database to cause the lock acquisition to hang or stall indefinitely. This could disrupt applications relying on filelock for synchronization.

Technologies: filelock (PyPI), Tox-Dev Filelock. Vendors: PyPI, Tox-Dev.

Quick answers

Is CVE-2026-112915 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-112915 being exploited in the wild.
How severe is CVE-2026-112915?: Medium severity, with a CVSS score of 5.5, published 20 October 2026.
Which products and versions are affected?: filelock (PyPI) >= 3.20.4, <= 4.2.0, ECOSYSTEM:introduced=3.20.4,fixed=4.2.1; Tox-Dev Filelock 3.20.4 to 4.2.1.
Is there a fix for CVE-2026-112915?: Yes. filelock (PyPI): upgrade to 4.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-112915 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-112915?: Check whether you run filelock (PyPI) or Tox-Dev Filelock 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

filelock (PyPI): upgrade to 4.2.1 or later
```
pip install "filelock>=4.2.1"
```

Technical details

The ReadWriteLock implementation in filelock stores lock state in a SQLite database without bounding schema complexity or query work. An attacker with local file system access can replace the database with a crafted version containing unbounded queries or expensive schema operations. When the lock is acquired (or initially opened in versions 3.20.4, or on every acquisition in 3.30.0+), the SQLite operations hang, causing a denial of service.

Affected products

tox-dev filelock 3.20.4 to 4.2.1

Identifiers

CVE-2026-112915
GHSA-cwqr-hh33-gh44

Timeline

2026-10-20: disclosed
2026-10-17: patched

References

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