CVE-2026-42767
Issue summary: An attacker-controlled CMP (Certificate Management Protocol) server could trigger a NULL pointer dereference in a CMP client application.
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 · 45th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- openssl/openssl
- Source
- openssl-security@openssl.org
References
- https://github.com/openssl/openssl/commit/61a86a8cd73546c9fea916f3d304c1293e05c046Patch
- https://github.com/openssl/openssl/commit/665d5254083affde9982efca7c41dd01cacc8774Patch
- https://github.com/openssl/openssl/commit/810b722f772652ad48042bcc7ab07e3414b11d0fPatch
- https://github.com/openssl/openssl/commit/b90ff3b1bd33b1c18e6a09936d097c2eddef8873Patch
- https://github.com/openssl/openssl/commit/e6f912907fc2ec82a0fd07aae55172c5e5e3d90dPatch
- https://openssl-library.org/news/secadv/20260609.txtVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.