Medium [CVE-2026-63073] untrusted sender DN used as format string in CMP response validation
This medium-severity Red Hat Linux advisory covers CVE-2026-63073 affecting Red Hat Developer Hub, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
A flaw was found in OpenSSL. A malicious CMP (Certificate Management Protocol) endpoint can send an unexpected distinguished name (DN) directly as the format string argument to ERR_raise_data(), causing the application to dereference and write to unrelated stack contents.
This can lead to a crash in the CMP client, resulting in a denial of service. Applications acting as a CMP client connecting to a malicious or intercepted CMP server are vulnerable to this issue, limiting its exposure.
Also, the CMP client needs to enforce an expected sender or use a pinned server certificate whose subject becomes the default expected sender. There is no controlled memory write, arbitrary-address read or path to code execution.
For these reasons, this vulnerability has been rated with a low severity. Red Hat severity: Low — CVSS 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).
Weakness: CWE-134. Affected Red Hat products: Red Hat Developer Hub; Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9; Red Hat Hardened Images; Red Hat OpenShift Container Platform 4.
Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Hardened Images; Red Hat Satellite 6; Red Hat Satellite Client as not affected. Red Hat does not currently list a fixing RHSA for this CVE.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 53 minutes ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 53 minutes ago·verify at source
Mitigation checklist
- Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Official advisory · high-confidence parse· fetched 53 minutes ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.