CVE-2026-53938

Publication date 9 September 2026

Last updated 16 September 2026


Ubuntu priority

Cvss 3 Severity Score

8.2 · High

Score breakdown

Description

OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). Prior to version 0.6.2.5, cjose's JWE decryption path for the AES Key Wrap key-management algorithms (`alg` = `A128KW`, `A192KW`, `A256KW`) does not validate the length of the attacker-supplied `encrypted_key` (JWE Encrypted Key) before unwrapping it into a fixed-size, heap-allocated Content Encryption Key (CEK) buffer. A remote, unauthenticated attacker who can submit a crafted JWE to an application that decrypts it with an AES-KW symmetric key can trigger an out-of-bounds heap write, corrupting the heap. This leads at minimum to a crash (denial of service) and, depending on the heap layout and allocator, may be leverageable for further memory-corruption impact. `cjose_jwe_import()` / `cjose_jwe_decrypt()` are pre-authentication entry points: they parse and process fully attacker-controlled input. Upgrade to cjose 0.6.2.5 to receive a patch. If upgrading is not immediately possible, reject the AES Key Wrap algorithms (`A128KW`/`A192KW`/`A256KW`) for untrusted JWEs at the application layer.

Status

Package Ubuntu Release Status
cjose 26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation

Severity score breakdown

CVSS version: CVSS v3.0

Base score 8.2 · High

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H


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