# CVE-2026-68162: sctp: avoid auth_enable sysctl UAF during netns teardown

> A use-after-free in the Linux kernel SCTP module during network namespace teardown allows attackers to potentially execute code or escalate privileges.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-95120, BELL-CVE-2026-68162, DEBIAN-CVE-2026-68162, GHSA-f75f-9mxv-wjhq, UBUNTU-CVE-2026-68162

## What is CVE-2026-68162?

CVE-2026-68162 is a high-severity use after free 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:

sctp: avoid auth_enable sysctl UAF during netns teardown

proc_sctp_do_auth() updates the SCTP control socket after changing
net.sctp.auth_enable. The handler gets the per-net SCTP state from
ctl->data, so an already opened sysctl file can still target a network
namespace while that namespace is being torn down.

SCTP previously registered its per-net sysctls from sctp_defaults_init(),
while the control socket is created later from sctp_ctrlsock_init(). This
exposed a window during initialization where auth_enable was writable
before net->sctp.ctl_sock existed, and a teardown window where auth_enable
stayed writable after inet_ctl_sock_destroy() had released the control
socket.

Move the per-net SCTP sysctl registration into sctp_ctrlsock_init() after
sctp_ctl_sock_init() succeeds, and unregister the sysctl table before
destroying the control socket in sctp_ctrlsock_exit(). If sysctl
registration fails after the control socket was created, destroy the
control socket in the same init path.

Make sctp_sysctl_net_unregister() tolerate a missing header and clear the
saved pointer so init-error and exit paths can safely share the unregister
helper.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-68162?


## How do I fix CVE-2026-68162?

Apply the vendor's patch.

## Is CVE-2026-68162 being exploited?

There is no known exploitation of CVE-2026-68162 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68162 and fix it if it is affected.

What it is: CVE-2026-68162 is a high-severity use after free 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-2026-68162 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-2026-68162/ (Markdown: https://insights.sbomify.com/CVE-2026-68162/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68162
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68162
- OSV: https://osv.dev/vulnerability/CVE-2026-68162

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68162/
Summaries are generated and may contain mistakes; the official description above is the record.