# GHSA-f87w-3j5w-v58p: CefSharp affected by incorrect handle provided in unspecified circumstances in Mojo on Windows

> Remote attackers can escape the sandbox and execute code via a malicious file in CefSharp on Windows.

- **Severity:** Not scored
- **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:** Yes
- **Published:** 12 Apr 2025

## What is GHSA-f87w-3j5w-v58p?

GHSA-f87w-3j5w-v58p is a vulnerability in CefSharp.OffScreen, published on 12 Apr 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

Incorrect handle provided in unspecified circumstances in Mojo in Google Chrome on Windows prior to 134.0.6998.177 allowed a remote attacker to perform a sandbox escape via a malicious file. (Chromium security severity: High)

https://nvd.nist.gov/vuln/detail/CVE-2025-2783
https://chromereleases.googleblog.com/2025/03/stable-channel-update-for-desktop_25.html
https://issues.chromium.org/issues/405143032

## Which versions are affected by GHSA-f87w-3j5w-v58p?

14 open source packages ship an affected version, including CefSharp.OffScreen, CefSharp.OffScreen.NetCore and CefSharp.WinForms.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `CefSharp.OffScreen` | NuGet | All versions | 134.3.90 |
| `CefSharp.OffScreen` | NuGet | All versions | 134.3.90 |
| `CefSharp.OffScreen.NetCore` | NuGet | All versions | 134.3.90 |
| `CefSharp.OffScreen.NetCore` | NuGet | All versions | 134.3.90 |
| `CefSharp.WinForms` | NuGet | All versions | 134.3.90 |
| `CefSharp.WinForms` | NuGet | All versions | 134.3.90 |
| `CefSharp.WinForms.NetCore` | NuGet | All versions | 134.3.90 |
| `CefSharp.WinForms.NetCore` | NuGet | All versions | 134.3.90 |
| `CefSharp.Wpf` | NuGet | All versions | 134.3.90 |
| `CefSharp.Wpf` | NuGet | All versions | 134.3.90 |
| `CefSharp.Wpf.HwndHost` | NuGet | All versions | 134.3.90 |
| `CefSharp.Wpf.HwndHost` | NuGet | All versions | 134.3.90 |
| `CefSharp.Wpf.NetCore` | NuGet | All versions | 134.3.90 |
| `CefSharp.Wpf.NetCore` | NuGet | All versions | 134.3.90 |

## How do I fix GHSA-f87w-3j5w-v58p?

Upgrade CefSharp.OffScreen to 134.3.90 or later.

## Is GHSA-f87w-3j5w-v58p being exploited?

There is no known exploitation of GHSA-f87w-3j5w-v58p in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-f87w-3j5w-v58p and fix it if it is affected.

What it is: GHSA-f87w-3j5w-v58p is a vulnerability in CefSharp.OffScreen, published on 12 Apr 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 GHSA-f87w-3j5w-v58p in the wild and no public exploit code.

Affected packages and fixed versions:
- CefSharp.OffScreen (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.OffScreen (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.OffScreen.NetCore (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.OffScreen.NetCore (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.WinForms (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.WinForms (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.WinForms.NetCore (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.WinForms.NetCore (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.Wpf (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.Wpf (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.Wpf.HwndHost (NuGet): affected all versions; fixed in 134.3.90
- CefSharp.Wpf.HwndHost (NuGet): affected all versions; fixed in 134.3.90

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/GHSA-f87w-3j5w-v58p/ (Markdown: https://insights.sbomify.com/GHSA-f87w-3j5w-v58p/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-f87w-3j5w-v58p

---
From sbomify Insights: https://insights.sbomify.com/GHSA-f87w-3j5w-v58p/
Summaries are generated and may contain mistakes; the official description above is the record.