# CVE-2026-94453: IKEv2 Use-After-Free bug when using IKE-over-TCP

> A use-after-free in Libreswan's pluto daemon allows remote attackers to cause denial of service or potentially execute code via IKE-over-TCP.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Oct 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-108027, DEBIAN-CVE-2026-94453, GHSA-59fc-px6w-3g8v, UBUNTU-CVE-2026-94453

## What is CVE-2026-94453?

CVE-2026-94453 is a high-severity use after free vulnerability in The Libreswan Project libreswan, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Libreswan's pluto daemon has a use-after-free vulnerability when a client connecting using IKE over TCP closes the connection and another packet (retransmit or malicious) is received for the same tuple. IKE state is retained in memory after the client closes the connection, storing a pointer to iface_endpoint inside ike_sa.sa->st_iface_endpoint. Once this invalid pointer is used, the daemon crashes and restarts. This vulnerability can be triggered before the remote peer has authenticated itself. Continued exploitation can lead to a denial of service. Remote code execution could be possible. The IKE over TCP option is not enabled by default; only configurations that contain listen-tcp=yes are affected.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-94453?


## How do I fix CVE-2026-94453?

Apply the vendor's patch.

## Is CVE-2026-94453 being exploited?

There is no known exploitation of CVE-2026-94453 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-94453 and fix it if it is affected.

What it is: CVE-2026-94453 is a high-severity use after free vulnerability in The Libreswan Project libreswan, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-94453 in the wild and no public exploit code.

Affected product: The Libreswan Project libreswan. 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-2026-94453/ (Markdown: https://insights.sbomify.com/CVE-2026-94453/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-94453
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-94453
- OSV: https://osv.dev/vulnerability/CVE-2026-94453

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-94453/
Summaries are generated and may contain mistakes; the official description above is the record.