CVE-2026-25480: Litestar's FileStore key canonicalization collisions allow response cache mixup/poisoning (ASCII ord + Unicode NFKD)

CVE-2026-25480 · Severity: low · CVSS 3.1 · Published 2026-02-09

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, FileStore maps cache keys to filenames using Unicode NFKD normalization and ord() substitution without separators, creating key collisions. When FileStore is used as response-cache backend, an unauthenticated remote attacker can trigger cache key collisions via crafted paths, causing one URL to serve cached responses of another (cache poisoning/mixup). This vulnerability is fixed in 2.20.0.

Technologies: litestar (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-25480 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-25480 being exploited in the wild.
How severe is CVE-2026-25480?
Low severity, with a CVSS score of 3.1, published 9 February 2026.
Which products and versions are affected?
litestar (PyPI) ECOSYSTEM:introduced=0,fixed=2.20.0, ECOSYSTEM:introduced=2.19.0,fixed=2.20.0.
Is there a fix for CVE-2026-25480?
Yes. litestar (PyPI): upgrade to 2.20.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-25480?
Check whether you run litestar (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

  • litestar (PyPI): upgrade to 2.20.0 or later
    pip install "litestar>=2.20.0"

Affected products

  • litestar (PyPI) ECOSYSTEM:introduced=0,fixed=2.20.0, ECOSYSTEM:introduced=2.19.0,fixed=2.20.0

Identifiers

  • CVE-2026-25480
  • GHSA-vxqx-rh46-q2pg
  • PYSEC-2026-2197

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