{
  "finding_id": "DF-3291",
  "status": "reproduced",
  "reproduced": 1,
  "impact": "none",
  "confidence": "certain",
  "verdict": "The GANN propagation gate (ttl-1 < 1 && !FWD) is always false when the default FWD flag is set, so TTL-exhausted GANNs are re-broadcast; pgann.gann_ttl = ie.gann_ttl - 1 in uint8 arithmetic wraps 0 to 255. Injected a well-formed ttl=0 GANN and captured the victims re-broadcast carrying TTL=0xff and hopcount+1 - the hop limit is defeated and the announcement gets a fresh 255-TTL budget (hopcount also wraps 255->0). Bounded only by per-gate seq dedup; protocol/logic defect with marginal amplification.",
  "exploit_chain": "established peer sends CAT_MESH GANN with ttl=0 -> condition false (FWD default) -> re-broadcast with ttl=255 -> next hops likewise never TTL-stop while FWD set",
  "evidence": "run.log (shared with DF-3290): tx[28] propagated GANN TTL=ff",
  "kernel_refs": [
    "sys/netproto/802_11/wlan/ieee80211_mesh.c:2690",
    "sys/netproto/802_11/wlan/ieee80211_mesh.c:2693",
    "sys/netproto/802_11/wlan/ieee80211_mesh.c:2694"
  ],
  "poc_changes": "harness step 22",
  "attempts": 1,
  "guest_uname": "DragonFly dfbsd 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026 root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC x86_64",
  "runtime_sec": 30,
  "guest_dirty": 0,
  "build_cmd": "sh findings/poc/DF-3286/build.sh",
  "run_cmd": "sh findings/poc/DF-3291/run.sh",
  "code_hash": "1b0e0b1a43331b1bc92e2614476535a88b88d3863db6ef91a36eead5c8ad7503",
  "notes": "impact none observed beyond the protocol violation (flood bounded by seq dedup)",
  "recommended_fix": "change && to || in the propagation condition (fix.diff hunk 6)",
  "fix_status": "fixed",
  "fix_kernel_uname": "DragonFly dfbsd 6.5-DEVELOPMENT #1: Thu Sep 10 05:34:08 UTC 2026 root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC x86_64 (fix kernel)",
  "fix_baseline_reproduced": 1,
  "fix_patched_reproduced": 0,
  "fix_verdict": "GANN ttl=0 no longer propagated (baseline: re-broadcast with TTL=0xff); && -> || gate stops TTL-exhausted GANNs",
  "fix_evidence": [
    "fix.log: no len-43 propagated frame after step 22"
  ]
}