CVE-2026-74355
HIGHCVE-2026-74355 is a high-severity (CVSS 8.2) vulnerability in Kernel. O3 Security confirms whether CVE-2026-74355 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
iommu/vt-d: Fix RB-tree corruption in probe error path
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:
iommu/vt-d: Fix RB-tree corruption in probe error path
The info->node RB-tree member is zero-initialized via kzalloc. If a device does not support ATS, the device_rbtree_insert() call is skipped. If a subsequent probe step fails, the error path jumps to device_rbtree_remove(), which misinterprets the zeroed node as a tree root and corrupts the device RB-tree.
Fix this by explicitly initializing the RB-node as empty using RB_CLEAR_NODE() during initialization and guarding the removal with RB_EMPTY_NODE().
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐧Linux | Kernel | ≥ 6.15.0&&< 6.18.40 | 6.18.40 |
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 6.18.40 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-74355 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-2026-74355 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-2026-74355. 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-2026-74355 in your dependencies?
O3 detects CVE-2026-74355 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.