Use of Hard-coded Cryptographic Key in cjose - CVE-2026-53939

Vulnerability identifier: #VU133240

CSH Severity: High

CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-53939

CWE-ID: CWE-321

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to disclose plaintext and modify protected content.

The vulnerability exists due to use of a hard-coded cryptographic key in JWE encryption in src/jwe.c when encrypting a JWE with an AES-CBC-HMAC content-encryption algorithm together with a key-management algorithm that generates a fresh CEK. A remote attacker can obtain a produced JWE and decrypt or forge its contents to disclose plaintext and modify protected content.

This affects only JWEs produced by the vulnerable encryption path; the issue does not affect the decryption path.

cjose
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server 12 SP5
Debian Linux
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Real Time 15
Server Applications Module
openSUSE Leap
openEuler
libcjose0
libcjose0-debuginfo
cjose-debugsource
libcjose-devel
cjose (Debian package)
cjose
cjose-debuginfo
cjose-devel

Install security update from vendor's website.

cjose - update to 0.6.2.6
libcjose0 - addressed in versions 0.6.1-7.8.1, 0.6.1-150100.4.9.1, 0.6.1-150600.18.3.1
libcjose0-debuginfo - addressed in versions 0.6.1-7.8.1, 0.6.1-150100.4.9.1, 0.6.1-150600.18.3.1
cjose-debugsource - addressed in versions 0.6.1-7.8.1, 0.6.1-150100.4.9.1, 0.6.1-150600.18.3.1
libcjose-devel - addressed in versions 0.6.1-150100.4.9.1, 0.6.1-150600.18.3.1
cjose (Debian package) - update to 0.6.2.3-1+deb13u1
cjose - update to 0.6.2.7-1
cjose-debuginfo - update to 0.6.2.7-1
cjose-debugsource - update to 0.6.2.7-1
cjose-devel - update to 0.6.2.7-1

• https://github.com/OpenIDC/cjose/security/advisories/GHSA-f6wf-pqg3-6wqq
• https://github.com/OpenIDC/cjose/commit/2a6e5bd969fa20059fb00913fb9f57d77ea6a4d9

• Use of Hard-coded Cryptographic Key in cjose
• Debian update for cjose
• SUSE update for cjose
• SUSE update for cjose
• SUSE update for cjose
• openEuler update for cjose