FORT-validator Vulnerable to RRDP Shared Snapshot Cache Poisoning

Summary

FORT Validator is a Resource Public Key Infrastructure (RPKI) relying-party validator that produces validated route-origin data. FORT Validator versions through 1.6.7 contain an origin-validation error in their RRDP processing: a delegated CA under the same Trust Anchor Locator (TAL) can reference a victim CA’s public RRDP notification and snapshot URLs, causing FORT’s URL-based download cache to report success after deleting the victim’s local snapshot. Following a routine victim publication, this can silently remove the victim’s VRPs and other signed objects from FORT’s output, potentially enabling route hijacking or loss of reachability. Version 1.6.8 contains a patch that rejects cross-origin RRDP snapshot and delta URLs; as a workaround, administrators can disable HTTP/RRDP with  --http.enabled=false  while keeping rsync enabled, although this can leave data unavailable or stale where rsync is not supported.