Authentication Bypass by Capture-replay in OpenClaw - CVE-2026-28449

 

Authentication Bypass by Capture-replay in OpenClaw - CVE-2026-28449

Published: April 7, 2026


Vulnerability identifier: #VU125084
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-28449
CWE-ID: CWE-294
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to trigger duplicate inbound processing.

The vulnerability exists due to authentication bypass by capture-replay in the Nextcloud Talk webhook path when handling previously valid signed webhook requests without durable replay suppression. A remote attacker can replay a captured signed request to trigger duplicate inbound processing.

The issue is limited to deployments using the Nextcloud Talk webhook integration and may be triggered after replay-window expiry or process restart.


Affected software

OpenClaw

How to mitigate CVE-2026-28449

Install security update from vendor's website.

OpenClaw - update to 2026.2.25

External References

Related Security Bulletins