Junglewise Threat Intelligence

OpenClaw IPv6 multicast SSRF classifier bypass

Severity: medium · CVSS 4 · Published 2026-03-03

Technologies: Openclaw. Vendors: Openclaw.

Executive brief

OpenClaw is a web application framework that includes server-side request blocking controls to prevent attackers from making unauthorized network requests. The SSRF (Server-Side Request Forgery) classifier failed to recognize IPv6 multicast addresses as blocked/private, allowing attackers to potentially bypass these protections. However, since OpenClaw restricts network requests to HTTP/HTTPS only, the practical risk is considered low defense-in-depth hardening.

Technical details

OpenClaw's SSRF address classifier vulnerability stems from an incomplete IPv6 private/internal range definition that omitted the multicast range (ff00::/8). This allowed IPv6 multicast literal addresses (e.g., ff02::1, ff05::1:3) to pass SSRF preflight validation checks. The vulnerability is a CWE-918 class issue (SSRF) requiring network-level attack capability. Although the bypass exists, the actual exploitability is limited since OpenClaw constrains network fetch/navigation paths to HTTP/HTTPS protocols only, reducing the attack surface. The fix was released in version 2026.2.25 (commit baf656bc).

Affected products

  • OpenClaw openclaw <= 2026.2.24

Timeline

  • 2026-03-03: disclosed
  • 2026-02-25: patched: Version 2026.2.25 released

References

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