DF-3275 / verdict.json
{ "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 } |