CVE-2026-35646: OpenClaw Remote Code Execution Vulnerability

MODERATE
Advisory Identifier: GHSA-mf5g-6r6f-ghhm
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CWE-307 CWE-521
Published
Advisory Summary

CVE-2026-35646 is a MODERATE remote code execution vulnerability (CWE-307: Improper Restriction of Excessive Authentication Attempts) affecting OpenClaw libraries in the npm ecosystem. The issue involves synology chat webhook pre-auth rate-limit bypass enables brute-force guessing of webhook token. Remediation is available by upgrading affected packages to version 2026.3.28.

CVE-2026-35646 at a Glance

CVE Identifier CVE-2026-35646
GHSA Identifier GHSA-mf5g-6r6f-ghhm
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-307: Improper Restriction of Excessive Authentication Attempts
Affected Product OpenClaw
Package Ecosystem npm
Published Date
Last Updated

How to Fix CVE-2026-35646

To remediate this vulnerability, upgrade all affected OpenClaw dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

openclaw fixed: 2026.3.28 
npm install openclaw@2026.3.28
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls openclaw

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-35646, inspect your project dependencies using npm:

npm ls openclaw

Analyze the terminal output to locate any version of OpenClaw in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2026.3.28), your application is affected.

Note: The npm ls openclaw command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-307: Improper Restriction of Excessive Authentication Attempts, where the product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame. In OpenClaw, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

## Summary Synology Chat Webhook Pre-Auth Rate-Limit Bypass Enables Brute-Force Guessing of Weak Webhook Token ## Affected Packages / Versions - Package: `openclaw` - Affected versions: `<= 2026.3.24` - First patched version: `2026.3.25` - Latest published npm version at verification time: `2026.3.24` ## Details Synology Chat webhook auth previously rejected invalid tokens without throttling repeated guesses, allowing brute-force attempts against weak webhook secrets. Commit `0b4d07337467f4d40a0cc1ced83d45ceaec0863c` adds repeated-guess throttling before auth failure responses. Verified vulnerable on tag `v2026.3.24` and fixed on `main` by commit `0b4d07337467f4d40a0cc1ced83d45ceaec0863c`. ## Fix Commit(s) - `0b4d07337467f4d40a0cc1ced83d45ceaec0863c`

CVE-2026-35646 Affected OpenClaw Versions

1 component(s)
Fixed Versions:
2026.3.28
Product / Package Ecosystem Affected Versions Fixed Version
openclaw
npm/openclaw
npm
< 2026.3.28
2026.3.28

References

GitHub Advisory / Wiki ADVISORY
https://github.com/openclaw/openclaw/security/advisories/GHSA-mf5g-6r6f-ghhm
NVD — CVE-2026-35646 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-35646
Security Fix Commit FIX COMMIT
https://github.com/openclaw/openclaw/commit/0b4d07337467f4d40a0cc1ced83d45ceaec0863c
OpenClaw Source Repository REPOSITORY
https://github.com/openclaw/openclaw
www.vulncheck.com/advisories/openclaw... WEB
https://www.vulncheck.com/advisories/openclaw-pre-authentication-rate-limit-bypass-in-webhook-token-validation

Frequently Asked Questions

What is CVE-2026-35646?
CVE-2026-35646 is a security vulnerability in OpenClaw involving Synology Chat Webhook Pre-Auth Rate-Limit Bypass Enables Brute-Force Guessing of Webhook Token under CWE-307: Improper Restriction of Excessive Authentication Attempts.
Which OpenClaw versions are affected?
Affected versions include releases prior to 2026.3.28 across affected packages: openclaw.
What version fixes CVE-2026-35646?
Upgrading to 2026.3.28 (or the latest patched release for your respective branch) resolves the vulnerability.
Is openclaw affected?
Yes, openclaw is affected in releases prior to 2026.3.28. Upgrade your dependency to 2026.3.28 or later.
What CWE is associated with CVE-2026-35646?
CVE-2026-35646 is classified under CWE-307: Improper Restriction of Excessive Authentication Attempts (The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.).
How can I check npm dependencies for CVE-2026-35646?
Run the dependency tree command: 'npm ls openclaw'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-mf5g-6r6f-ghhm",
  "modified" : "2026-04-10T20:25:07Z",
  "published" : "2026-03-29T15:50:09Z",
  "aliases" : [ "CVE-2026-35646" ],
  "summary" : "OpenClaw: Synology Chat Webhook Pre-Auth Rate-Limit Bypass Enables Brute-Force Guessing of Webhook Token",
  "details" : "## Summary\n\nSynology Chat Webhook Pre-Auth Rate-Limit Bypass Enables Brute-Force Guessing of Weak Webhook Token\n\n## Affected Packages / Versions\n\n- Package: `openclaw`\n- Affected versions: `<= 2026.3.24`\n- First patched version: `2026.3.25`\n- Latest published npm version at verification time: `2026.3.24`\n\n## Details\n\nSynology Chat webhook auth previously rejected invalid tokens without throttling repeated guesses, allowing brute-force attempts against weak webhook secrets. Commit `0b4d07337467f4d40a0cc1ced83d45ceaec0863c` adds repeated-guess throttling before auth failure responses.\n\nVerified vulnerable on tag `v2026.3.24` and fixed on `main` by commit `0b4d07337467f4d40a0cc1ced83d45ceaec0863c`.\n\n## Fix Commit(s)\n\n- `0b4d07337467f4d40a0cc1ced83d45ceaec0863c`",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "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"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "openclaw"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2026.3.28"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/openclaw/openclaw/security/advisories/GHSA-mf5g-6r6f-ghhm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-35646"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openclaw/openclaw/commit/0b4d07337467f4d40a0cc1ced83d45ceaec0863c"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/openclaw/openclaw"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/openclaw-pre-authentication-rate-limit-bypass-in-webhook-token-validation"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-307", "CWE-521" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-29T15:50:09Z",
    "nvd_published_at" : null
  }
}