CVE-2026-28389

Issue summary: During processing of a crafted CMS EnvelopedData message with KeyAgreeRecipientInfo a NULL pointer dereference can happen. Impact summary: Applications that process attacker-controlled CMS data may crash before authentication or cryptographic operations occur resulting in Denial of Service. When a CMS EnvelopedData message that uses KeyAgreeRecipientInfo is processed, the optional parameters field of KeyEncryptionAlgorithmIdentifier is examined without checking for its presence. This results in a NULL pointer dereference if the field is missing. Applications and services that call CMS_decrypt() on untrusted input (e.g., S/MIME processing or CMS-based protocols) are vulnerable. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

The following products are affected by CVE-2026-28389 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-28389.

URL	Resource
https://github.com/openssl/openssl/commit/16cea4188e0ea567deb4f93f85902247e67384f5
https://github.com/openssl/openssl/commit/785cbf7ea3b5a6f5adf0c1ccb92b79d89c35c616
https://github.com/openssl/openssl/commit/7b5274e812400cacb6f3be4c2df5340923fa807f
https://github.com/openssl/openssl/commit/c6725634e089eb2b634b10ede33944be7248172a
https://github.com/openssl/openssl/commit/f80f83bc5fd036bc47d773e8b15a001e2b4ce686
https://nvd.nist.gov/vuln/detail/CVE-2026-28389
https://openssl-library.org/news/secadv/20260407.txt
https://www.cve.org/CVERecord?id=CVE-2026-28389