{"id":"UBUNTU-CVE-2026-53938","details":"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.","modified":"2026-09-16T14:01:42.902831275Z","published":"2026-09-09T00:17:00Z","upstream":["CVE-2026-53938"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-53938"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-53938"}],"affected":[{"package":{"name":"cjose","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/cjose?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.1-3ubuntu1","0.5.1+dfsg1-1","0.5.1+dfsg1-2","0.5.1+dfsg1-2build1","0.6.0+dfsg1-1","0.6.0+dfsg1-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libcjose0","binary_version":"0.6.0+dfsg1-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-53938.json"}},{"package":{"name":"cjose","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/cjose?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6.1+dfsg1-1","0.6.1+dfsg1-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.6.1+dfsg1-1ubuntu0.1","binary_name":"libcjose0"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-53938.json"}},{"package":{"name":"cjose","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/cjose?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6.1+dfsg1-1","0.6.1+dfsg1-3","0.6.1+dfsg1-3ubuntu1","0.6.1+dfsg1-3ubuntu1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libcjose0","binary_version":"0.6.1+dfsg1-3ubuntu1.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-53938.json"}},{"package":{"name":"cjose","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/cjose?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6.2.2-1","0.6.2.2-1build1","0.6.2.2-1build2","0.6.2.2-1build3"],"ecosystem_specific":{"binaries":[{"binary_name":"libcjose0","binary_version":"0.6.2.2-1build3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-53938.json"}},{"package":{"name":"cjose","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/cjose?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6.2.3-1","0.6.2.4-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.6.2.4-1","binary_name":"libcjose0"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-53938.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H"},{"type":"Ubuntu","score":"medium"}]}