Vulnerability in Openclaw
CVE-2026-28449
OpenClaw versions prior to 2026.2.25 lack durable replay state for Nextcloud Talk webhook events, allowing valid signed webhook requests to be replayed without suppression. Attackers can capture and replay previously valid signed webhook requests to trigger duplicate inbound message processing and cause integrity or availability issues.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
EPSS: 0.005 (38.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 38.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Openclaw — versions 0
Weakness classification (CWE)
References
- github.com/openclaw/openclaw/security/advisories/GHSA-r9q5-c7qc-p26w (vendor-advisory, Mitigation, Vendor Advisory, third-party-advisory)
- github.com/openclaw/openclaw/commit/d512163d686ad6741783e7119ddb3437f493dbbc (Patch, patch)
- www.vulncheck.com/advisories/openclaw-webhook-replay-attack-via-missing-durable… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-28449?
- CVE-2026-28449 is a medium-severity vulnerability in Openclaw, classified under Authentication Bypass by Capture-replay. CVSS score: 6.5/10. Published 2026-03-19.
- How severe is CVE-2026-28449?
- Medium severity. CVSS v3 base score is 6.5 out of 10.