Auth bypass in Openclaw Nextcloud-Talk
CVE-2026-28474
OpenClaw's Nextcloud Talk plugin versions prior to 2026.2.6 accept equality matching on the mutable actor.name display name field for allowlist validation, allowing attackers to bypass DM and room allowlists. An attacker can change their Nextcloud display name to match an allowlisted user ID and gain unauthorized access to restricted conversations.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.008 (56.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.4% 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: 0.008 · change: +0.004
Affected products
- Openclaw Nextcloud-Talk — versions 0
- Openclaw
Weakness classification (CWE)
References
- github.com/openclaw/openclaw/security/advisories/GHSA-r5h9-vjqc-hq3r (vendor-advisory, Patch, Vendor Advisory)
- github.com/openclaw/openclaw/commit/6b4b6049b47c3329a7014509594647826669892d (Patch, patch)
- www.vulncheck.com/advisories/openclaw-nextcloud-talk-allowlist-bypass-via-actor… (Third Party Advisory, Broken Link, third-party-advisory)
Frequently asked questions
- What is CVE-2026-28474?
- CVE-2026-28474 is a critical-severity vulnerability in Openclaw Nextcloud-Talk, classified under Incorrect Authorization. CVSS score: 9.8/10. Published 2026-03-05.
- How severe is CVE-2026-28474?
- Critical severity. CVSS v3 base score is 9.8 out of 10.