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TI-2026-20591 Aliases CVE-2026-25480GHSA-vxqx-rh46-q2pg

FileStore key canonicalization collisions allow response cache mixup/poisoning (ASCII ord + Unicode NFKD)

Priority LOW 35CWE-176Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, FileStore maps cache keys to filenames using Unicode NFKD normalization and ord() substitution without separators, creating key collisions. When FileStore is used as response-cache backend, an unauthenticated remote attacker can trigger cache key collisions via crafted paths, causing one URL to serve cached responses of another (cache poisoning/mixup). This vulnerability is fixed in 2.20.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0046 40th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed litestar (litestar-org): 2.20.0litestar (PyPI): 2.20.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
litestar-orglitestarbefore 2.20.02.20.0Patch availableCNA
—litestar (PyPI)2.19.0 to before 2.20.02.20.0Patch availableGHSA-vxqx-rh46-q2pg
  • litestar Vendorlitestar-org Affected before 2.20.0 Fixed in 2.20.0 Patch available CNA
  • litestar (PyPI) Vendor— Affected 2.19.0 to before 2.20.0 Fixed in 2.20.0 Patch available GHSA-vxqx-rh46-q2pg

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:litestar:litestar:*:*:*:*:*:*:*:*before 2.20.0Vulnerablelitestar-org
  • cpe:2.3:a:litestar:litestar:*:*:*:*:*:*:*:* Versions before 2.20.0 Vulnerable ·litestar-org

Remediation

  • Fix · CNA litestar (litestar-org) Fixed in 2.20.0
  • Fix · GHSA-vxqx-rh46-q2pg litestar (PyPI) Fixed in 2.20.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-25480
  2. 2026-10-03 Alias added: GHSA-vxqx-rh46-q2pg

References

Exploit 1

Patch 1

Advisory 1

Other 3

  • TI-2024-35241 Litestar allows unbounded resource consumption (DoS vulnerability) CVSS 4.0HIGH 8.2
  • TI-2026-20590 Litestar has an AllowedHosts validation bypass due to unescaped regex metacharacters in configured host patterns CVSS 3.1MEDIUM 6.5
  • TI-2026-20589 Litestar has a CORS origin allowlist bypass due to unescaped regex metacharacters in allowed origins CVSS 3.1HIGH 7.4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences