CVE-2026-25479
Litestar has an AllowedHosts validation bypass due to unescaped regex metacharacters in configured host patterns
MEDIUM 6.5EPSS 0.5%
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.
- Affected
- litestar-org · litestar
- CVSS v3.1 GITHUB
- 6.5 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS
- 0.46% chance of exploitation in the next 30 days, 38th percentile
- Published
- 2026-02-09
- Updated
- 2026-02-10
Proof-of-concept exploits (1)
Security advisories
- litestar-org/litestar/security/advisories/GHSA-93ph-p7v4-hwh4
- litestar-org/litestar/commit/06b36f481d1bfea6f19995cfb4f203aba45c4ace
- https://docs.litestar.dev/2/release-notes/changelog.html#2.20.0