CVE-2026-25479
Prior to 2.20.0, in litestar.middleware.allowed_hosts, allowlist entries are compiled into regex patterns in a way that allows regex metacharacters to retain special meaning (e.g., . matches any character).
Does this matter?
Lower severity and a low EPSS score (0.33%). Track it; it rarely justifies an emergency change on its own.
Description
Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, in litestar.middleware.allowed_hosts, allowlist entries are compiled into regex patterns in a way that allows regex metacharacters to retain special meaning (e.g., . matches any character). This enables a bypass where an attacker supplies a host that matches the regex but is not the intended literal hostname. This vulnerability is fixed in 2.20.0.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- EPSS
- 0.33% probability · 26th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-185
- Affected
- litestar/litestar
- Source
- security-advisories@github.com
References
- https://docs.litestar.dev/2/release-notes/changelog.html#2.20.0Release Notes
- https://github.com/litestar-org/litestar/commit/06b36f481d1bfea6f19995cfb4f203aba45c4acePatch
- https://github.com/litestar-org/litestar/releases/tag/v2.20.0Release Notes
- https://github.com/litestar-org/litestar/security/advisories/GHSA-93ph-p7v4-hwh4Exploit, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.