{"id":"DEBIAN-CVE-2026-63076","details":"Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can contain a parameter of a different type, which is then dereferenced as an invalid pointer.  Impact summary: A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a Denial of Service.  CWE: CWE-476: NULL Pointer Dereference  Description: When verifying the password-based MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The parameter type returned by X509_ALGOR_get0() was never consulted.  This happens during protection verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only precondition is that PBM verification is reachable. On the server side this is reached from OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected messages, and on the client side from CMP response validation against a malicious or on-path (MITM) server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled memory write, and no path to code execution. CMP is a specialized feature that an application must explicitly enable.  FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.","modified":"2026-09-25T05:34:38.439279527Z","published":"2026-08-25T13:19:26.543Z","upstream":["CVE-2026-63076"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-63076"}],"affected":[{"package":{"name":"openssl","ecosystem":"Debian:12","purl":"pkg:deb/debian/openssl?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.22-1~deb12u1"}]}],"versions":["3.0.10-1","3.0.10-1~deb12u1","3.0.11-1","3.0.11-1~deb12u1","3.0.11-1~deb12u2","3.0.12-1","3.0.12-2","3.0.13-1~deb12u1","3.0.13-1~deb12u2","3.0.14-1~deb12u1","3.0.14-1~deb12u2","3.0.15-1~deb12u1","3.0.16-1~deb12u1","3.0.17-1~deb12u1","3.0.17-1~deb12u2","3.0.17-1~deb12u3","3.0.18-1~deb12u1","3.0.18-1~deb12u2","3.0.19-1~deb12u1","3.0.19-1~deb12u2","3.0.20-1~deb12u1","3.0.20-1~deb12u2","3.0.9-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-63076.json"}},{"package":{"name":"openssl","ecosystem":"Debian:13","purl":"pkg:deb/debian/openssl?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.5.7-1~deb13u2"}]}],"versions":["3.5.1-1","3.5.1-1+deb13u1","3.5.2-1","3.5.3-1","3.5.4-1","3.5.4-1~deb13u1","3.5.4-1~deb13u2","3.5.5-1","3.5.5-1~deb13u1","3.5.5-1~deb13u2","3.5.6-1~deb13u1","3.5.6-1~deb13u2","3.5.7-1~deb13u1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-63076.json"}},{"package":{"name":"openssl","ecosystem":"Debian:14","purl":"pkg:deb/debian/openssl?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.6.4-1"}]}],"versions":["3.5.1-1","3.5.2-1","3.5.3-1","3.5.4-1","3.5.4-1~deb13u1","3.5.4-1~deb13u2","3.5.5-1","3.5.5-1~deb13u1","3.5.5-1~deb13u2","3.5.6-1~deb13u1","3.5.6-1~deb13u2","3.5.7-1~deb13u1","3.5.7-1~deb13u2","3.6.0-1","3.6.0-2","3.6.0~~alpha1-1","3.6.0~~beta1-1","3.6.1-1","3.6.1-2","3.6.1-3","3.6.2-1","3.6.3-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-63076.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:N/A:H"}]}