CVE-2024-56375 — Integer Underflow (Wrap or Wraparound) in Fort-validator

An integer underflow was discovered in Fort 1.6.3 and 1.6.4 before 1.6.5. A malicious RPKI repository that descends from a (trusted) Trust Anchor can serve (via rsync or RRDP) a Manifest RPKI object containing an empty fileList. Fort dereferences (and, shortly afterwards, writes to) this array during a shuffle attempt, before the validation that would normally reject it when empty. This out-of-bounds access is caused by an integer underflow that causes the surrounding loop to iterate infinitely.…