CVE-2026-74470
CVE-2026-74470 is a security vulnerability in Kernel. O3 Security confirms whether CVE-2026-74470 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
scsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write
Real-World Exposure
KernelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Linux packages — download data is not available via public APIs for these ecosystems.
Description
In the Linux kernel, the following vulnerability has been resolved:
scsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write
resp_report_zones() sizes the reply buffer from the CDB allocation length. The v3 fix rounds alloc_len up with ALIGN() before deriving the descriptor count:
rep_max_zones = (ALIGN((u64)alloc_len, RZONES_DESC_HD) -
RZONES_DESC_HD) >> ilog2(RZONES_DESC_HD);
arr_len = (u64)RZONES_DESC_HD * (rep_max_zones + 1);
For alloc_len in 0xFFFFFFC1..0xFFFFFFFF, ALIGN() rounds up to 0x100000000, so arr_len is 4 GB. On 32-bit, kzalloc()'s size_t is 32-bit and truncates 0x100000000 to 0; kzalloc(0) returns ZERO_SIZE_PTR, which passes the !arr check, and desc = arr + 64 is then dereferenced in the loop -> out-of-bounds write / panic.
Clamp rep_max_zones to devip->nr_zones. The loop already stops at sdebug_capacity (after nr_zones zones), so a report can never hold more than nr_zones descriptors; the clamp does not change the report, it only bounds arr_len to (nr_zones + 1) * RZONES_DESC_HD, a real device property that can never reach 0x100000000.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐧Linux | Kernel | ≥ 5.16.0&&< 6.6.151 | 6.6.151 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Kernel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update Kernel to 6.6.151 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-74470 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-74470 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-74470. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-74470 in your dependencies?
O3 detects CVE-2026-74470 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.