Auth bypass in Openclaw

CVE-2026-53851

OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (22.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 22.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-53851: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-53851?
CVE-2026-53851 is a medium-severity vulnerability in Openclaw, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-06-16.
How severe is CVE-2026-53851?
Medium severity. CVSS v3 base score is 5.3 out of 10.