OpenClaw has a IPv6 multicast SSRF classifier bypass
Date: 2026-03
Affected: npm/openclaw
Attack vector: ssrf
Category: vulnerability-disclosure
Severity: Medium
CWE: CWE-918

### Summary OpenClaw's SSRF IP classifier did not treat IPv6 multicast literals (`ff00::/8`) as blocked/private-internal. This allowed literal multicast hosts to pass SSRF preflight checks. ### Impact A bypass in address classification existed for IPv6 multicast literals. OpenClaw's network fetch/navigation paths are constrained to HTTP/HTTPS and this was triaged as low-severity defense-in-depth hardening. ### Affected Packages / Versions - Package: `openclaw` (npm) - Affected versions: `<= 2026.2.24` - Patched versions: `>= 2026.2.25` ### Technical Details The IPv6 private/internal range set omitted `multicast`, so addresses like `ff02::1` and `ff05::1:3` were not classified as blocked by the shared SSRF classifier. ### Fix Commit(s) - `baf656bc6fd7f83b6033e6dbc2548ec75028641f` ### Release Process Note `patched_versions` is pre-set to the planned next npm release (`2026.2.25`). Once that release is published on npm, the advisory is published. OpenClaw thanks @zpbrent for reporting.


Mitigations:

Architectural layers (MAESTRO):