OpenCloud Reva has a Public Link Exploit

Exploitation

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

CVSS

8.2 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

EPSS

• CVE-2026-23989: 0.30% estimated exploitation activity in the next 30 days; percentile 22.75 (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.

Impact A security issue was discovered in Reva based products that enables a malicious user to bypass the scope validation of a public link, allowing it to access resources outside the scope of a public link. Details Public link shares in OpenCloud are bound to a specific scope (usually a file or directory). Anonymous users accessing resources via this public link share are only allowed to access the share resource itself and, in case of a directory or space root, all child resources of it. Due to a bug in the GRPC authorization middleware of the "Reva" component of OpenCloud a malicious user is able to bypass the scope verification. By exploiting this via the the "archiver" service this can be leveraged to create an archive (zip or tar-file) containing all resources that this creator of the public link has access to. It is not possible to bypass the public link scope via "normal" WebDAV requests so it is not possible to exploit this vulnerability via WebDAV. Patches Update to…

Published by the source

5 Feb 2026, 20:32 UTC

Last modified by the source

6 Feb 2026, 21:42 UTC

Source last checked

26 Oct 2026, 15:14 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9j2f-3rj3-wgpg

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# Patch Next advisory brief: CVE-2026-23989

Advisory: OpenCloud Reva has a Public Link Exploit
IDs: CVE-2026-23989, GHSA-9j2f-3rj3-wgpg
Record: https://patchnext.com/advisories/cve-2026-23989 (revision 1, source checked 26 Oct 2026, 15:14 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/opencloud-eu/reva/v2 2.42.3, 2.40.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/opencloud-eu/reva/v2: affected <= 2.40.1; >= 2.41.0, < 2.42.3; fixed in 2.42.3, 2.40.3

## Suggested inspection (read-only)
- Go github.com/opencloud-eu/reva/v2: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/opencloud-eu/reva/v2.
- 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-9j2f-3rj3-wgpg (GitHub-reviewed advisory GHSA-9j2f-3rj3-wgpg lists affected ranges: Go github.com/opencloud-eu/reva/v2 >=0 =2.41.0 <2.42.3)

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