Is there a patch available for CVE-2026-35646?

Yes, a patch is available for CVE-2026-35646. Update the affected software to the latest version immediately.

Openclaw CVE-2026-35646

Q: What is the CVSS score of CVE-2026-35646?

CVE-2026-35646 has a CVSS 4.0 base score of 6.3 (Medium). CVSS vector: 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.1%.

EUVD-2026-21144 MEDIUM

Improper Restriction of Excessive Authentication Attempts (CWE-307)

2026-04-09 VulnCheck

GHSA-59xc-5v89-r7pr

Authentication Bypass Openclaw

6.3

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

EUVD ID Assigned

Apr 09, 2026 - 21:45 euvd

EUVD-2026-21144

Analysis Generated

Apr 09, 2026 - 21:45 vuln.today

Patch released

Apr 09, 2026 - 21:45 nvd

Patch available

CVE Published

Apr 09, 2026 - 21:27 nvd

MEDIUM 6.3

Blast Radius

ecosystem impact

† from your stack dependencies † transitive graph · vuln.today resolves 4-path depth

3 npm packages depend on openclaw (3 direct, 0 indirect)

Ecosystem-wide dependent count for version 2026.3.28.

DescriptionCVE.org

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.

AnalysisAI

OpenClaw before version 2026.3.25 allows unauthenticated remote attackers to bypass pre-authentication rate limiting on webhook token validation, enabling brute-force attacks against weak webhook secrets through rapid successive requests. The vulnerability stems from absent throttling on invalid token rejection attempts, permitting attackers to enumerate valid tokens without login credentials or triggering defensive rate-limiting mechanisms.

Technical ContextAI

OpenClaw's webhook authentication mechanism validates incoming webhook tokens prior to processing webhook payloads. The vulnerability is rooted in CWE-307 (Improper Restriction of Excessive Authentication Attempts), a class of weakness where authentication systems fail to implement rate limiting or account lockout protections. The affected component lacks throttling or exponential backoff on repeated failed authentication attempts. Attackers can craft successive HTTP requests containing guessed webhook tokens; each invalid token is rejected without introducing delays or tracking failures across requests. This design flaw is particularly dangerous because webhook secrets are often weak or poorly randomized, making brute-force enumeration computationally feasible within acceptable attack timeframes. The CPE string cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:*:*:* indicates all versions of the OpenClaw application are potentially affected until the patched version is deployed.

RemediationAI

Vendor-released patch: OpenClaw 2026.3.25 or later. Immediately upgrade to the patched version using standard package management or release distribution channels. The upstream fix is documented in commit 0b4d07337467f4d40a0cc1ced83d45ceaec0863c on the OpenClaw GitHub repository (https://github.com/openclaw/openclaw/commit/0b4d07337467f4d40a0cc1ced83d45ceaec0863c). Consult the official security advisory at https://github.com/openclaw/openclaw/security/advisories/GHSA-mf5g-6r6f-ghhm for detailed upgrade instructions and any dependency-related changes. As an interim compensating control pending patch deployment, restrict network access to webhook endpoints via firewall rules or API gateway policies, allowing only trusted source IP ranges to submit webhook requests; however, this is a temporary mitigation and does not address the underlying vulnerability.