Vulnerability Database

328,409

Total vulnerabilities in the database

OpenClaw affected by denial of service via unbounded webhook request body buffering

Summary

Multiple webhook handlers accepted and buffered request bodies without a strict unified byte/time limit. A remote unauthenticated attacker could send oversized payloads and cause memory pressure, degrading availability.

Details

Affected packages:

  • openclaw (npm): <2026.2.12
  • clawdbot (npm): <=2026.1.24-3

Root cause:

  • Webhook code paths buffered request payloads without consistent maxBytes + timeoutMs enforcement.
  • Some SDK-backed handlers parse request bodies internally and needed stream-level guards.

Attack shape:

  • Send very large JSON payloads or slow/incomplete uploads to webhook endpoints.
  • Observe elevated memory usage and request handler pressure.

Impact

Remote unauthenticated availability impact (DoS) via request body amplification/memory pressure.

Patch details (implemented)

  • Added shared bounded request-body helper in src/infra/http-body.ts.
  • Exported helper in src/plugin-sdk/index.ts for extension reuse.
  • Migrated webhook body readers to shared helper for:
    • LINE
    • Nextcloud Talk
    • Google Chat
    • Zalo
    • BlueBubbles
    • Nostr profile HTTP
    • Voice-call
    • Gateway hooks
  • Added stream guards for SDK handlers that parse request bodies internally:
    • Slack
    • Telegram
    • Feishu
  • Added explicit Express JSON body limit handling for MS Teams webhook path.
  • Standardized failure responses:
    • 413 Payload Too Large
    • 408 Request Timeout

Tests

  • Added regression tests:
    • src/infra/http-body.test.ts
    • src/line/monitor.read-body.test.ts
    • extensions/nextcloud-talk/src/monitor.read-body.test.ts
  • Focused webhook/security test suite passes for patched paths.

Remediation

Upgrade to the first release containing this patch.

Credits

Thanks @vincentkoc for reporting.

CVSS v3:

  • Severity: Unknown
  • Score:
  • AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWEs:

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

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