# CVE-2026-96760: Authlib library contains a signature‑verification bypass vulnerability

Status: published. Published: 2026-09-28. Updated: 2026-11-11.

Authlib (v1.8.0 and below) contains a signature verification bypass vulnerability. The JsonWebSignature.deserialize_json() method accepts a JSON Serialization JWS object and returns the payload as successfully verified without checking for a signature and without requiring a cryptographic key.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Authlib / Authlib: 1.8.0 (affected). Source: CNA: certcc

## Severity and prioritization

- CVSS 3.1: 9.8 (critical); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H; source: ADP: CISA-ADP

- CVSS 3.1: 9.8 (critical); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H; source: NVD: 134c704f-9b21-4f2e-91b3-4a467353bcc0

- CISA KEV: No listing in collected sources

- EPSS: 0.43% as of 2026-11-10; percentile 37.91%

- SSVC: exploitation none; automatable yes; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-347, CWE-670, CWE-358, CWE-20

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/authlib/authlib (CNA: certcc)

- https://kb.cert.org/vuls/id/762428 (CNA: certcc)

- https://www.kb.cert.org/vuls/id/762428 (ADP: CVE)

- https://github.com/authlib/authlib (cret@cert.org)

- https://kb.cert.org/vuls/id/762428 (cret@cert.org)

- https://www.kb.cert.org/vuls/id/762428 (af854a3a-2127-422b-91ae-364da2661108)

## Provenance

- CNA: certcc: https://www.cve.org/CVERecord?id=CVE-2026-96760; retrieved 2026-11-11; source updated 2026-11-11

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-96760; retrieved 2026-11-11; source updated 2026-11-11

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-96760; retrieved 2026-11-11; source updated Not reported

Revision: 6150a522f0fd8287ca7002225ab502b33fd4337ca7426836a79d0dcb0b6ddb0a

Canonical: https://y2.dev/cve/CVE-2026-96760

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