Red Hat Security Advisory: cjose security update
Description
A critical security vulnerability (CVE-2026-53939) exists in the cjose C library, which implements Javascript Object Signing and Encryption (JOSE). The flaw involves the use of an all-zero Content Encryption Key for AES-CBC-HMAC JWE encryption, weakening the encryption and potentially compromising data confidentiality. Red Hat has issued a security update addressing this issue for Red Hat Enterprise Linux 10.0 Extended Update Support and related products. Users are advised to apply the update as detailed in the Red Hat advisory.
Affected software
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Weaknesses
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Machine-generated threat intelligence
Technical Analysis
The cjose library, used for Javascript Object Signing and Encryption (JOSE), contained a critical vulnerability (CVE-2026-53939) where OpenIDC/cjose used an all-zero Content Encryption Key for AES-CBC-HMAC JWE encryption. This cryptographic flaw undermines the security of encrypted JSON Web Encryption (JWE) tokens by using a predictable key, potentially allowing attackers to bypass encryption protections. Red Hat has released a security update for multiple Red Hat Enterprise Linux 10.0 Extended Update Support variants and related CodeReady Linux Builder products to fix this issue.
Potential Impact
The vulnerability compromises the confidentiality of data encrypted with the affected cjose library by using a fixed all-zero encryption key, which can allow attackers to decrypt or forge encrypted messages. This impacts any system relying on the vulnerable version of cjose for secure JOSE operations, potentially exposing sensitive information.
Mitigation Recommendations
Red Hat has released an official security update that fixes this vulnerability. Users of affected Red Hat Enterprise Linux 10.0 Extended Update Support and related products should apply the update as described in the Red Hat advisory (https://access.redhat.com/articles/11258). No additional mitigation steps are required beyond applying the official patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:83224
- Cve Count
- 1
- State
- PUBLISHED
Threat ID: 6ad7ec432cdf04f6566b9edb
Added to database: 10/20/2026, 22:33:39 UTC
Last enriched: 10/20/2026, 22:42:48 UTC
Last updated: 10/20/2026, 22:48:16 UTC
Views: 6
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