CVE-2026-25478 json
Litestar has a CORS origin allowlist bypass due to unescaped regex metacharacters in allowed origins
published 9mo ago modified 3mo ago also EUVD-2026-6496 , GHSA-2p2x-hpg8-cqp2 , PYSEC-2026-2195
- cvss
- 7.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
Summary
Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, CORSConfig.allowed_origins_regex is constructed using a regex built from configured allowlist values and used with fullmatch() for validation. Because metacharacters are not escaped, a malicious origin can match unexpectedly. The check relies on allowed_origins_regex.fullmatch(origin). This vulnerability is fixed in 2.20.0.
Patch / fix
- pypi litestar 2.20.0
- litestar litestar 2.20.0
Is CVE-2026-25478 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 8mo ago
Exploit prediction
0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N |
| GitHub | 3.1 | 7.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N |
| OSV | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | litestar | >=2.19.0, <2.20.0 <2.20.0 |
2.20.0 |
Affected products
- litestar-org litestar
Classification
- Weakness
-
- CWE-942 Permissive Cross-domain Security Policy with Untrusted Domains
References
-
github.com
/litestar-org/litestar/commit/eb87703b309efcc0d1b087dcb12784e76b003d5a
web, patch
-
github.com
/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2
web, exploit, vendor-advisory, evidence
-
docs.litestar.dev
/2/release-notes/changelog.html#2.20.0
web, release-notes, advisory
-
github.com
/litestar-org/litestar/releases/tag/v2.20.0
web, release-notes, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-25478
advisory
-
github.com
/litestar-org/litestar
package
Sources
- CVE List CVE-2026-25478
- GitHub Advisory GHSA-2p2x-hpg8-cqp2
- NVD CVE-2026-25478
- OSV PYSEC-2026-2195
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.