Quick answers
- Is CVE-2026-63076 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-63076 being exploited in the wild.
- How severe is CVE-2026-63076?
- High severity, with a CVSS score of 7.5, published 25 August 2026.
- Which products and versions are affected?
- OpenSSL <UNKNOWN>.
- Is there a fix for CVE-2026-63076?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-63076 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-63076?
- Check whether you run OpenSSL at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a null pointer dereference (CWE-476) in OpenSSL's CMP password-based MAC (PBM) protection verification. When processing a CMP message, the library calls X509_ALGOR_get0() to retrieve the protectionAlg parameter, which returns both the parameter type and value pointer. The code only checks that the value pointer is not NULL before casting it to ASN1_STRING and treating it as a PBMParameter, but never validates the parameter's ASN.1 type. An attacker can craft a message with a malformed parameter of a different type, causing invalid pointer dereference and denial of service. No authentication or knowledge of the PBM shared secret is required; the vulnerability is reachable on the server side via OSSL_CMP_SRV_process_request() for any CMP server accepting PBM-protected messages, and on the client side through response validation. The issue results in reliable denial of service only, with no memory disclosure or code execution path.
Affected products
- OpenSSL OpenSSL <UNKNOWN>
Timeline
- 2026-08-25: disclosed