# CVE-2025-11680: Out-of-bounds Write in libwebsockets PNG parsing

> An attacker can cause a crash via heap buffer overflow in libwebsockets when visiting a malicious site with a crafted PNG, requiring specific compilation flags.

- **Severity:** Medium 5.9 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 20 Oct 2025
- **Updated:** 20 Oct 2025
- **Also known as:** GHSA-7h7w-vjr9-r6m8

## What is CVE-2025-11680?

CVE-2025-11680 is a medium-severity memory corruption vulnerability in warmcat libwebsockets, published on 20 Oct 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Out-of-bounds Write in unfilter_scanline in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to write past a heap allocated buffer possibly causing a crash, when the user visits an attacker controlled website that contains a crafted PNG file with a big width value that causes an integer overflow which value is used for determining the size of a heap allocation.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2025-11680?


## How do I fix CVE-2025-11680?

No fix has been published for CVE-2025-11680 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-11680 being exploited?

There is no known exploitation of CVE-2025-11680 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-11680 and fix it if it is affected.

What it is: CVE-2025-11680 is a medium-severity memory corruption vulnerability in warmcat libwebsockets, published on 20 Oct 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2025-11680 in the wild and no public exploit code.

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-2025-11680/ (Markdown: https://insights.sbomify.com/CVE-2025-11680/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-11680
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-11680
- OSV: https://osv.dev/vulnerability/CVE-2025-11680

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-11680/
Summaries are generated and may contain mistakes; the official description above is the record.