CVE-2026-82454

The Omnivore API (packages/api) before the fix in commit abf53d6 contains an authentication bypass in Apple sign-in token verification. The decodeAppleToken function extracted the 'alg' field from the attacker-supplied JWT header and passed it as the sole allowed algorithm to jwt.verify(). Using jsonwebtoken v8 (which does not validate key/algorithm compatibility), an attacker can set alg=HS256 and sign a forged token using Apple's publicly available RSA public key as the HMAC secret, bypassing signature verification and impersonating any Apple-linked account.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/omnivore-app/omnivore
https://github.com/omnivore-app/omnivore/commit/abf53d6508755d3d22a994e28e370a9193ea977a
https://github.com/omnivore-app/omnivore/pull/4652
https://www.vulncheck.com/advisories/omnivore-before-android-0.227.0-authentication-bypass-via-apple-sign-in

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-29 14:16

Updated : 2026-08-31 19:17

NVD link : CVE-2026-82454

Mitre link : CVE-2026-82454

CVE.ORG link : CVE-2026-82454

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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