# CVE-2026-63076: OpenSSL CMP password protection verification null pointer dereference

Source: https://junglewise.ai/threats/cve-2026-63076-openssl-cmp-password-protection-verification-null-pointer  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-25. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-63076 · Severity: high · CVSS 7.5 · Published 2026-08-25

OpenSSL's CMP (Certificate Management Protocol) feature, which some applications use to manage digital certificates, contains a flaw in how it verifies password-protected messages. An attacker can send a specially crafted message that causes the application to crash, resulting in service unavailability. This affects both CMP servers accepting password-protected requests and CMP clients communicating with compromised servers.

Technologies: [OpenSSL](https://junglewise.ai/threats/technologies/openssl). Vendors: [OpenSSL](https://junglewise.ai/threats/vendors/openssl).

## 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

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