NULL Pointer Dereference in CRMF EncryptedValue Decryption
CVE-2026-42767

Currently unrated

Key Information:

Vendor

OpenSSL

Status
Vendor
CVE Published:
9 June 2026

What is CVE-2026-42767?

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.

Affected Version(s)

OpenSSL 4.0.0 < 4.0.1

OpenSSL 3.6.0 < 3.6.3

OpenSSL 3.5.0 < 3.5.7

References

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Zhanpeng Liu (Tencent Xuanwu Lab)
Guannan Wang (Tencent Xuanwu Lab)
Guancheng Li (Tencent Xuanwu Lab)
Igor Ustinov
Tomáš Mráz
.