CVE-2026-53939

Einstufung nach Quelle

Trivys eigenes Label ist CRITICAL. Kritisch laut Red Hat, AlmaLinux, Oracle, Rocky Linux. Niedriger laut Amazon (hoch).

Beschreibung

OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). In versions 0.6.1 through 0.6.2.5, when cjose encrypts a JWE using an AES-CBC-HMAC content-encryption algorithm (`A128CBC-HS256`, `A192CBC-HS384`, or `A256CBC-HS512`) together with any key-management algorithm that generates a fresh content-encryption key (CEK), the CEK is all zero bytes instead of being randomly generated. The resulting JWE is therefore encrypted and authenticated under a fixed, publicly known key, so anyone who obtains the JWE can recover the plaintext and forge or modify the content. This is fixed in version 0.6.2.6 by `_cjose_jwe_set_cek_aes_cbc()` generating the CEK from `RAND_bytes`. A regression test asserts that the `encrypted_key` differs across two encryptions for each AES-CBC-HMAC variant. Until upgrading, for data encrypted with cjose, three options are available. Use an AES-GCM `enc` (`A128GCM` / `A192GCM` / `A256GCM`) instead of an AES-CBC-HMAC `enc`, use `alg=dir` with a caller-supplied CEK, or avoid using cjose for JWE encryption with the affected algorithm pair. These are mitigations for new ciphertexts only; data already encrypted under the zero key remains compromised and should be re-encrypted (and any secrets it contained rotated).

Betroffene Pakete und behobene Versionen

Referenzen

• https://access.redhat.com/errata/RHSA-2026:80605
• https://access.redhat.com/security/cve/CVE-2026-53939
• https://bugzilla.redhat.com/2530243
• https://bugzilla.redhat.com/show_bug.cgi?id=2530243
• https://creativecommons.org/licenses/by/4.0/
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-53939
• https://errata.almalinux.org/10/ALSA-2026-80605.html
• https://errata.rockylinux.org/RLSA-2026:80605