CVE-2026-74747
HIGHCVE-2026-74747 is a high-severity (CVSS 7.8) vulnerability in Kernel. O3 Security confirms whether CVE-2026-74747 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
ipvs: revalidate ihl to prevent out-of-bounds access
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:
ipvs: revalidate ihl to prevent out-of-bounds access
While the outer IP header is already pulled into the skb head, we must be careful and revalidate the embedded headers after reading them from the skb frags to prevent out-of-bounds access.
One such place reported by Sashiko is ip_vs_nat_icmp() where local process can change the ihl field and after skb_ensure_writable() we can see larger value which is a problem for the ip_send_check(cih) calls.
Add check to drop the packet if the ihl field is changed.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐧Linux | Kernel | ≥ 2.6.12&&< 7.1.10 | 7.1.10 |
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 7.1.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-74747 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-2026-74747 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-2026-74747. 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-2026-74747 in your dependencies?
O3 detects CVE-2026-74747 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.