CVE-2026-64261
HIGHCVE-2026-64261 is a high-severity (CVSS 7.8) vulnerability in Kernel. O3 Security confirms whether CVE-2026-64261 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
fuse-uring: Avoid use-after-free in fuse_uring_async_stop_queues
Blast Radius
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:
fuse-uring: Avoid use-after-free in fuse_uring_async_stop_queues
fuse_uring_async_stop_queues() might run when the last reference on ring->queue_refs was already dropped.
In order to avoid an early destruction a reference on struct fuse_conn is now taken before starting fuse_uring_async_stop_queues() and that reference is only released when that delayed work queue terminates.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐧Linux | Kernel | ≥ 6.14.0&&< 6.18.39 | 6.18.39 |
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 6.18.39 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-64261 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-2026-64261 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-2026-64261. 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-2026-64261 in your dependencies?
O3 detects CVE-2026-64261 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.