CVE-2026-42767

Description

Issue summary: An attacker-controlled CMP (Certificate Management Protocol) server could trigger a NULL pointer dereference in a CMP client application. Impact summary: A NULL pointer dereference causes a crash of the application and a Denial of Service. An attacker controlling a CMP server (or acting as a man-in-the-middle) could craft a CMP response containing a CRMF (Certificate Request Message Format) CertRepMessage with an EncryptedValue structure where the symmAlg field has an algorithm OID but no parameters field. When the OpenSSL CMP client processes this response, the NULL dereference occurs, causing a crash of the CMP client. Applications that process untrusted CMP/CRMF messages may be affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

PUBLISHED Reserved 2026-04-29 | Published 2026-06-09 | Updated 2026-06-10 | Assigner openssl

Problem types

CWE-476 NULL Pointer Dereference

Product status

Credits

Zhanpeng Liu (Tencent Xuanwu Lab) reporter

Guannan Wang (Tencent Xuanwu Lab) reporter

Guancheng Li (Tencent Xuanwu Lab) reporter

Bhabani Sankar Das reporter

Igor Ustinov remediation developer

Tomáš Mráz remediation developer

References

openssl-library.org/news/secadv/20260609.txt (OpenSSL Advisory) vendor-advisory

github.com/...ommit/b90ff3b1bd33b1c18e6a09936d097c2eddef8873 (4.0.1 git commit) patch

github.com/...ommit/e6f912907fc2ec82a0fd07aae55172c5e5e3d90d (3.6.3 git commit) patch

github.com/...ommit/810b722f772652ad48042bcc7ab07e3414b11d0f (3.5.7 git commit) patch

github.com/...ommit/665d5254083affde9982efca7c41dd01cacc8774 (3.4.6 git commit) patch

github.com/...ommit/61a86a8cd73546c9fea916f3d304c1293e05c046 (3.0.21 git commit) patch

cve.org (CVE-2026-42767)

nvd.nist.gov (CVE-2026-42767)

Download JSON