CVE-2026-35646 (GCVE-0-2026-35646)

Vulnerability from cvelistv5 – Published: 2026-04-09 21:27 – Updated: 2026-04-10 13:57 X_Open Source
VLAI
Title
OpenClaw < 2026.3.25 - Pre-Authentication Rate-Limit Bypass in Webhook Token Validation
Summary
OpenClaw before 2026.3.25 contains a pre-authentication rate-limit bypass vulnerability in webhook token validation that allows attackers to brute-force weak webhook secrets. The vulnerability exists because invalid webhook tokens are rejected without throttling repeated authentication attempts, enabling attackers to guess weak tokens through rapid successive requests.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-307 - Improper Restriction of Excessive Authentication Attempts
Assigner
References
Impacted products
Vendor Product Version
OpenClaw OpenClaw Affected: 0 , < 2026.3.25 (semver)
Unaffected: 2026.3.25 (semver)
Create a notification for this product.
Date Public
2026-03-26 00:00
Credits
Peng Zhou (@zpbrent)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.