# CVE-2026-68286: drop_monitor: perform u64_stats updates under IRQ-disabled section

> A race condition in the Linux kernel drop_monitor allows local attackers to corrupt statistics or cause denial of service on 32-bit systems.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Aug 2026
- **Updated:** 3 Oct 2026
- **Also known as:** AZL-95229, BELL-CVE-2026-68286, DEBIAN-CVE-2026-68286, GHSA-xcpv-vj7m-3hh9, UBUNTU-CVE-2026-68286

## What is CVE-2026-68286?

CVE-2026-68286 is a vulnerability in Linux, published on 10 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

drop_monitor: perform u64_stats updates under IRQ-disabled section

In net_dm_packet_trace_kfree_skb_hit() and net_dm_hw_trap_packet_probe(),
u64_stats_update_begin() / u64_stats_inc() / u64_stats_update_end() were
called after spin_unlock_irqrestore(&...drop_queue.lock, flags), when local
IRQs had already been re-enabled.

Tracepoint probes can execute in IRQ or softirq context. On 32-bit
architectures, u64_stats_update_begin() disables preemption but not interrupts,
relying on seqcount writes. If a nested interrupt occurs on the same CPU during
the 64-bit stats update, the reentrant seqcount update can corrupt the
seqcount state or stats value.

Fix this by performing the 64-bit per-CPU stats update before releasing
drop_queue.lock via spin_unlock_irqrestore(), ensuring local interrupts remain
disabled during the u64_stats update.

## Which versions are affected by CVE-2026-68286?


## How do I fix CVE-2026-68286?

Apply the vendor's patch.

## Is CVE-2026-68286 being exploited?

There is no known exploitation of CVE-2026-68286 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68286 and fix it if it is affected.

What it is: CVE-2026-68286 is a vulnerability in Linux, published on 10 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-68286 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-68286/ (Markdown: https://insights.sbomify.com/CVE-2026-68286/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68286
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68286
- OSV: https://osv.dev/vulnerability/CVE-2026-68286

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68286/
Summaries are generated and may contain mistakes; the official description above is the record.