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CVE-2026-45363

CVE.org · Published

Historical CVEsJSONAI instructions

Record status
Published
Identifier year (not publication year)
2026
Source publication
Source updated
Imported by cveboard
Source snapshot
cve_2026-10-24_midnight_baseline ·

Plain text

CNA source text (English)

`jwt` (Ruby gem) - empty-key HMAC bypass

ruby-jwt is a Ruby implementation of the RFC 7519 OAuth JSON Web Token standard. Prior to 2.10.3 and 3.2.0, JWT.decode(token, '', true, algorithm: 'HS256') accepts an attacker-forged token because OpenSSL::HMAC.digest('SHA256', '', payload) returns a valid digest under an empty key and no empty-key precondition exists in the HMAC algorithm. The same path is reached when a keyfinder block or key_finder: argument returns an empty string, nil, or an array containing nil for an unknown key, affecting HS256, HS384, and HS512 verification through JWT.decode and JWT::EncodedToken#verify_signature!. This issue is fixed in versions 2.10.3 and 3.2.0.

Scoped product and version facts

Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.

Exploitation unknown; this catalogue does not assess exploitation.

ruby-jwt

Vendor
jwt
Product
ruby-jwt
Platforms
Unknown
Default status
Unknown
ruby-jwt · Scoped product and version facts
Version (version)Status (status)Version scheme (versionType)Exclusive end (lessThan)Inclusive end (lessThanOrEqual)Status changes (at → status)
< 2.10.3affectedUnavailableUnavailableUnavailableNone listed
>= 3.0.0, < 3.2.0affectedUnavailableUnavailableUnavailableNone listed