OpenClaw before 2026.3.28 contains a missing rate limiting vulnerability in the Nextcloud Talk webhook authentication that allows attackers to brute-force weak shared secrets. Attackers who can reach the webhook endpoint can exploit this to forge inbound webhook events by repeatedly attempting authentication without throttling.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Openclaw Openclaw
cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*
|
— |
2026.3.28
|
References 3
https://github.com/openclaw/openclaw/security/advisories/GHSA-9528-x887-j2fp
GitHub Security Advisory (GHSA-9528-x887-j2fp)
https://github.com/openclaw/openclaw/commit/e403decb6e20091b5402780a7ccd2085f98…
Patch Commit
https://www.vulncheck.com/advisories/openclaw-brute-force-attack-via-missing-ra…
VulnCheck Advisory: OpenClaw < 2026.3.28 - Brute Force Attack via Missing Rate Limiting on Webhook Shared Secret Authentication