Auth bypass in Ceph
CVE-2026-50152
Ceph is an open-source distributed storage platform providing object, block, and file storage. In versions prior to 20.2.4 and 19.2.6, the Monitor subscription handler fails to properly authorize access to the configuration-key store, allowing any CephX user with only `mon allow r` capabilities to read the entire store by sending a single crafted MMonSubscribe message. The config-key store holds sensitive secrets including OSD LUKS disk-encryption passphrases and, on cephadm-managed clusters, the SSH private key that cephadm uses to reach every host in the cluster. Because that key grants root on every node under the default cephadm configuration, a low-privileged read-only account can escalate to full cluster and host compromise. This issue is fixed in versions 20.2.4 and 19.2.6
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L.
Affected products
- Ceph — versions >= 19.0.0, < 19.2.6, >= 20.0.0, < 20.2.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-50152?
- CVE-2026-50152 is a critical-severity vulnerability in Ceph, classified under Improper Authorization. CVSS score: 9.1/10. Published 2026-08-28.
- How severe is CVE-2026-50152?
- Critical severity. CVSS v3 base score is 9.1 out of 10.