# CVE-2026-74490: tipc: avoid use-after-free in poll trace queue dumps

> A use-after-free vulnerability in the Linux kernel TIPC module allows attackers to cause denial of service or potentially execute code via race conditions in poll trace queue dumps.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-96378, BELL-CVE-2026-74490, DEBIAN-CVE-2026-74490, GHSA-5445-w6x8-6hfq, UBUNTU-CVE-2026-74490

## What is CVE-2026-74490?

CVE-2026-74490 is a high-severity use after free vulnerability in Linux, published on 15 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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

tipc: avoid use-after-free in poll trace queue dumps

TIPC socket tracepoints dump queue state through tipc_sk_dump(). Most
queue-dump callsites already serialize that walk under the socket lock or
sk->sk_lock.slock, but tipc_poll() calls trace_tipc_sk_poll(...,
TIPC_DUMP_ALL, ...) without holding either lock.

That lets the poll trace path reach tipc_list_dump() and backlog head/tail
dumping while another context dequeues and frees an skb, leaving the trace
helper dereferencing a stale queue entry.

Stop the unlocked poll trace site from requesting queue dumps. Other queue
dump trace callsites keep their existing output under the locking they
already provide, while poll still emits the event itself without walking
live queue members from an unlocked context.

## Which versions are affected by CVE-2026-74490?


## How do I fix CVE-2026-74490?

Apply the vendor's patch.

## Is CVE-2026-74490 being exploited?

There is no known exploitation of CVE-2026-74490 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74490 and fix it if it is affected.

What it is: CVE-2026-74490 is a high-severity use after free vulnerability in Linux, published on 15 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-74490 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-2026-74490/ (Markdown: https://insights.sbomify.com/CVE-2026-74490/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74490
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74490
- OSV: https://osv.dev/vulnerability/CVE-2026-74490

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74490/
Summaries are generated and may contain mistakes; the official description above is the record.