DF-5241

PROBE_INQUIRY_BASIC_DV1/DV2: bcmp() reads SHORT_INQUIRY_LENGTH (36) bytes from a kmalloc(additional_length+5) buffer as small as 6 bytes (device-controlled heap OOB read)

Summary

probestart sizes the DV inquiry buffer from the device's own re-fetched additional_length (as few as 6 bytes when it answers 0 the second time) but probedone bcmps a fixed 36 bytes - up to 30 bytes past the allocation, feeding the DV1 comparison decision. Malicious SCSI/ATAPI target (USB gadget, untrusted SAN) comparison-oracle OOB read; exercised live in the DF-5240 run ('inquiry data fails comparison at DV1 step'). min()-bound fix.

Discussion (0)

No comments yet.

Severity: Low
Status: new
Bucket: Kernel memory leaks / uninitialized disclosure
Confidence: certain
Pass: 2 · GLM 5.3 second pass
CVSS 3.1: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE: CWE-125
File: sys/bus/cam/cam_xpt.c
Lines: 5867-6471
Area: hw
Discovered: 2026-10-01
Updated: 2026-10-01

Team triage

untriaged

priority: — · owner: —

PoC verification

untested

Status: untested
Reproduced: no
Impact: heap OOB comparison oracle / race-gated UAF / accounting drift
Confidence: certain
Tested: 2026-10-01 15:15:43
Attempts: 0
Runtime: —
Code hash: —
Guest: 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
Build cmd: n/a
Run cmd: n/a

jump to evidence pack ↓

Fix verification

not_testable

Fix status: not_testable
Baseline reproduced: no
Patched reproduced: no
Confidence: certain
Tested: 2026-10-01 15:15:43
Runtime: —
Kernel: per-fix-DF-5241
fix.diff: findings/poc/DF-5241/fix.diff
Runner: df-bsd-reviewer

jump to fix verification ↓

PoC verification

Evidence pack

findings/poc/DF-5241 · 1 files

File	Type	Description	Size
verdict.json	file		1.0 KB	view raw

Fix verification

not_testable

baseline no→ patch + rebuild →patched clean

per-fix-DF-5241

Confirmed kernel references

sys/bus/cam/cam_xpt.c:5867

Detail

Evidence (decisive lines)

static trace in finding markdown (DF-5241 live message in findings/poc/DF-5240/run.log)

Verified recommended fix

see finding markdown

Verdict

untested (Low oracle / Medium race-gated source-verified / Info accounting; Phase V not required per contract - DF-5241 exercised live inside the DF-5240 run)