Auth bypass in Openbao
CVE-2026-55775
OpenBao is an open source identity-based secrets management system. Prior to 2.5.5, OpenBao users granted capabilities on /sys/namespaces/root within a non-root namespace could exploit special handling of the literal root path in namespace canonicalization. The /sys/namespaces/* endpoint family can resolve its containing namespace through a path prefix or X-Vault-Namespace header. ACL checks occurred before root canonicalized to an empty path, causing /sys/namespaces/root to resolve to the system backend's containing namespace and allowing permitted lookups, deletion, locking, or custom metadata changes against that direct containing namespace. The root namespace and arbitrary unrelated namespaces are not affected, and available operations depend on the capabilities granted on the path and subpaths such as /api-lock. This issue is fixed in version 2.5.5.
Published · last modified .
EPSS exploit prediction
EPSS: 0.005 (41.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Openbao — versions < 2.5.5
Weakness classification (CWE)
References
- github.com/openbao/openbao/security/advisories/GHSA-mwr2-wmgp-crj6
- github.com/openbao/openbao/pull/3308
- github.com/openbao/openbao/pull/3311
- github.com/openbao/openbao/commit/216b623cdde161eb7798bd095fc874c2174a4dd2
- github.com/openbao/openbao/commit/d3c1cc64b1ae7f9868b5c3e80b8b11671f0d97ae
- github.com/openbao/openbao/releases/tag/v2.5.5
- github.com/openbao/openbao/releases/tag/v2.6.0