CVE-2026-42767

Low

No strong exploitation signal.

CVSS base

5.9 MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — probability of exploitation (30 days)

0.6%

45.2th percentile

CISA KEV

Not listed

Weakness / dates

CWE-476

Published 2026-06-09 · modified 2026-07-23

CVSS breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector	N	Network
Attack Complexity	H	High
Privileges Required	N	None
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	N	None
Integrity	N	None
Availability	H	High

Timeline

2026-06-09 — Published (NVD)
2026-07-23 — Last modified (NVD)

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.

Affected

openssl

References

Official: NVD · CVE.org