OpenBao's System Backend allows Unauthorized Management of the containing Namespace

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

2.3 · CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-55775: 0.48% estimated exploitation activity in the next 30 days; percentile 41.73 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A user that is granted namespace management (/sys/namespaces) capabilities within a non-root namespace ("the victim namespace") can abuse special handling of the literal path "root" in namespace path canonicalization to manage the victim namespace itself. Details Several endpoints under /sys/namespaces/ accept a namespace path segment that is canonicalized and then appended to the path of the sys mount's containing namespace (set via path prefix or X-Vault-Namespace header) to determine the absolute path of the namespace to operate on. Given the special namespace path "root" canonicalizes to en empty path (""), when passed as /sys/namespaces/root, the resulting absolute namespace path remains equal to the sys mount's containing namespace. Given ACLs are evaluated before namespace path canonicalization, this allows users with capabilities on /sys/namespaces/root within any given namespace to operate on the namespace itself instead. Impact Users that were granted the required…

Published by the source

19 Jun 2026, 21:42 UTC

Last modified by the source

19 Jun 2026, 21:42 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-mwr2-wmgp-crj6

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# Patch Next advisory brief: CVE-2026-55775

Advisory: OpenBao's System Backend allows Unauthorized Management of the containing Namespace
IDs: CVE-2026-55775, GHSA-mwr2-wmgp-crj6
Record: https://patchnext.com/advisories/cve-2026-55775 (revision 1, source checked 26 Oct 2026, 15:24 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 2.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: github.com/openbao/openbao 0.0.0-20260617103935-d3c1cc64b1ae. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/openbao/openbao: affected < 0.0.0-20260617103935-d3c1cc64b1ae; >= 0.1.0, <= 2.5.4; fixed in 0.0.0-20260617103935-d3c1cc64b1ae

## Suggested inspection (read-only)
- Go github.com/openbao/openbao: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/openbao/openbao.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-mwr2-wmgp-crj6 (GitHub-reviewed advisory GHSA-mwr2-wmgp-crj6 lists affected ranges: Go github.com/openbao/openbao >=0 =0.1.0 <=2.5.4)

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