# CVE-2026-78161: warmcat libwebsockets LECP CBOR Recording lecp.c report_raw_cbor out-of-bounds write

> Remote attackers can trigger an out-of-bounds write in libwebsockets LECP CBOR recording, potentially leading to code execution or crashes.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Aug 2026
- **Updated:** 24 Aug 2026
- **Also known as:** BELL-CVE-2026-78161, DEBIAN-CVE-2026-78161, GHSA-83xp-6qr9-g946, UBUNTU-CVE-2026-78161

## What is CVE-2026-78161?

CVE-2026-78161 is a medium-severity memory corruption vulnerability in warmcat libwebsockets, published on 24 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was found in warmcat libwebsockets 4.5.0. Impacted is the function report_raw_cbor of the file lib/misc/lecp.c of the component LECP CBOR Recording. The manipulation results in out-of-bounds write. The attack can be launched remotely. The exploit has been made public and could be used. The patch is identified as 1d44554a1bb262db63ff4e240152a9deecd99054. It is best practice to apply a patch to resolve this issue.

Weakness: CWE-787 (Out-of-bounds Write), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-78161?


## How do I fix CVE-2026-78161?

Apply the vendor's patch.

## Is CVE-2026-78161 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-78161 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-78161 and fix it if it is affected.

What it is: CVE-2026-78161 is a medium-severity memory corruption vulnerability in warmcat libwebsockets, published on 24 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-78161 exists.

Affected product: warmcat libwebsockets. 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-2026-78161/ (Markdown: https://insights.sbomify.com/CVE-2026-78161/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-78161
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-78161
- OSV: https://osv.dev/vulnerability/CVE-2026-78161

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-78161/
Summaries are generated and may contain mistakes; the official description above is the record.