Summary
OpenClaw: Feishu webhook reads and parses unauthenticated request bodies before signature validation
Feishu webhook reads and parses unauthenticated request bodies before signature validation
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
Feishu webhook handling previously parsed JSON before signature validation, which let unauthenticated callers force full JSON parsing work before rejection. Commit 5e8cb22176e9235e224be0bc530699261eb60e53 reads the raw request body, validates the signature first, and only then parses JSON.
Verified vulnerable on tag v2026.3.24 and fixed on main by commit 5e8cb22176e9235e224be0bc530699261eb60e53.
Fix Commit(s)
5e8cb22176e9235e224be0bc530699261eb60e53
Impact
Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-35640? CVE-2026-35640 is a medium-severity uncontrolled resource consumption vulnerability in openclaw (npm), affecting versions < 2026.3.28. It is fixed in 2026.3.28. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
- Which versions of openclaw are affected by CVE-2026-35640? openclaw (npm) versions < 2026.3.28 is affected.
- Is there a fix for CVE-2026-35640? Yes. CVE-2026-35640 is fixed in 2026.3.28. Upgrade to this version or later.
- Is CVE-2026-35640 exploitable, and should I be worried? Whether CVE-2026-35640 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-35640 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-35640? Upgrade
openclawto 2026.3.28 or later.