Litestar's CORS origin allowlist has a bypass due to unescaped regex metacharacters in allowed origins

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0044, the 38th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 15:04 UTC First seen by agentprime
2. 31 Oct 2026, 15:04 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-2p2x-hpg8-cqp2
• OSV: GHSA-2p2x-hpg8-cqp2
• github.com/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2
• nvd.nist.gov/vuln/detail/CVE-2026-25478
• github.com/litestar-org/litestar/commit/eb87703b309efcc0d1b087dcb12784e76b003d5a
• docs.litestar.dev/2/release-notes/changelog.html#2.20.0
• github.com/litestar-org/litestar
• github.com/litestar-org/litestar/releases/tag/v2.20.0

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.