VulnerabilityAnalyzed

CVE-2026-42767

Issue summary: An attacker-controlled CMP (Certificate Management Protocol) server could trigger a NULL pointer dereference in a CMP client application.

MEDIUM 5.9EPSS 0.56%

Does this matter?

Lower severity and a low EPSS score (0.56%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1: 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.56% probability · 46th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-476
Affected: openssl/openssl
Source: openssl-security@openssl.org

EPSS trend

EPSS 0.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.