⬢ DragonFlyBSD Kernel Audit
DF-3275 / verdict.json
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{
 "finding_id": "DF-3275",
 "status": "not_reproduced",
 "reproduced": 0,
 "poc_path": "findings/poc/DF-3275",
 "artifact_dir": "findings/poc/DF-3275",
 "build_cmd": "cc -O -o <prog> <prog>.c   (on the guest)",
 "run_cmd": "(no arg)",
 "code_hash": "52a3643ffe93e9187d3e006e2714c47a37c706a4d3f4c7bc24f8d8104ea25c4d",
 "build_log": "(inline)",
 "run_log": "VERDICT.md",
 "impact": "none",
 "confidence": "likely",
 "verdict": "The PAP/CHAP compares are verbatim early-exit bcmp (4330-4336 / 4069-4071) - the code property is certain - but the timing oracle could NOT be measured on this shared-KVM guest: rejection time for a 16-byte compare is ~1 cycle regardless of prefix (memcmp differences below scheduler/clock noise). No remote timing channel demonstrated; treat as hardening.",
 "exploit_chain": "",
 "evidence": "misc3.log DF-3275 (df3275 timing table: ~0.9-1.4 cycles/reject, non-monotone)",
 "kernel_refs": [
  "sys/net/sppp/if_spppsubr.c:4330-4336",
  "sys/net/sppp/if_spppsubr.c:4069-4071"
 ],
 "poc_changes": "",
 "attempts": 3,
 "guest_uname": "DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 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": 60,
 "guest_dirty": 0,
 "runner": "df-bsd-reviewer",
 "notes": "",
 "recommended_fix": "",
 "fix_status": "not_testable",
 "fix_verdict": "Fix = constant-time compare (loop all bytes, accumulate XOR) at both sites; not A/B-able here since no oracle was measurable.",
 "fix_baseline_reproduced": null,
 "fix_patched_reproduced": null
}