Missing Rate Limiting Vulnerability in OpenClaw's Telegram Webhook Authentication
CVE-2026-35628

6.3MEDIUM

Key Information:

Vendor

Openclaw

Status
Openclaw
Vendor
CVE Published:
9 April 2026

What is CVE-2026-35628?

OpenClaw prior to version 2026.3.25 is vulnerable to brute-force attacks due to the absence of rate limiting in its Telegram webhook authentication mechanism. This vulnerability allows attackers to repeatedly attempt to guess weak webhook secrets without any restrictions, significantly increasing the risk of unauthorized access. To mitigate this risk, users must update to the latest version that incorporates the necessary rate limiting protections.

Affected Version(s)

OpenClaw 0 < 2026.3.25

OpenClaw 2026.3.25

References

https://github.com/openclaw/openclaw/security/advisories/...
third-party-advisory
https://github.com/openclaw/openclaw/commit/c2c136ae9517d...
patch
https://www.vulncheck.com/advisories/openclaw-brute-force...
third-party-advisory

CVSS V4

Score:
6.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Peng Zhou (@zpbrent)
.