CVE-2026-25480
Cache Poisoning in Litestar FileStore via Key Collision
Publication date: 2026-02-09
Last updated on: 2026-02-17
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| litestar | litestar | to 2.20.0 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-176 | The product does not properly handle when an input contains Unicode encoding. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the Litestar ASGI framework prior to version 2.20.0. The issue arises because the FileStore component maps cache keys to filenames using Unicode NFKD normalization and ord() substitution without separators, which can cause different cache keys to collide.
When FileStore is used as a response-cache backend, an unauthenticated remote attacker can exploit this by crafting specific paths that cause cache key collisions. This results in one URL serving the cached response intended for another URL, effectively causing cache poisoning or mixup.
The vulnerability is fixed in Litestar version 2.20.0.
How can this vulnerability impact me? :
This vulnerability can impact you by allowing an unauthenticated remote attacker to cause cache poisoning or mixup. This means that users may receive incorrect or unintended cached responses for certain URLs.
Such behavior can lead to information disclosure, as sensitive data intended for one user or endpoint might be served to another. It can also undermine the integrity and reliability of the application responses.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade Litestar to version 2.20.0 or later, where the issue with FileStore cache key collisions has been fixed.