The CVE-2025-2783 vulnerability in CefSharp stems from an incorrect handle being provided in Mojo IPC (Inter-Process Communication) in Google Chrome on Windows. Mojo is Chrome’s messaging system for cross-process communication, and improper handle management can lead to sandbox escape. In this case, a malicious file could exploit the mishandled handle to break out of Chrome’s sandbox, allowing arbitrary code execution at the system level. The flaw affects versions prior to 134.0.6998.177, where a remote attacker could craft a payload to trigger the vulnerability, bypassing security restrictions.
DailyCVE Form:
Platform: CefSharp/Chrome
Version: < 134.0.6998.177
Vulnerability: Sandbox Escape
Severity: High
Date: 2025-04-12
What Undercode Say:
Exploit Analysis:
- Attacker crafts malicious file embedding Mojo IPC calls.
- Exploit triggers incorrect handle assignment in renderer process.
3. Malicious payload escapes sandbox via elevated privileges.
Protection Commands:
Update Chrome/CefSharp: sudo apt-get update && sudo apt-get install --only-upgrade cefsharp
Detection Code (Python):
import os
def check_chrome_version():
version = os.popen("google-chrome --version").read()
if "134.0.6998.177" not in version:
print("Vulnerable! Update immediately.")
Mitigation Steps:
1. Apply patch 134.0.6998.177.
- Disable Mojo IPC if unused via Chrome flags:
--disable-mojo-core
3. Monitor process handles via Sysinternals Handle.exe:
handle.exe -p chrome.exe
Exploit PoC (Theoretical):
// Malicious Mojo message triggering handle leak mojo::Message msg; msg.set_handle(mojo::InvalidHandle()); // Force incorrect assignment
Log Analysis:
Check Chrome logs for repeated Mojo errors:
grep "Mojo handle error" /var/log/chrome/chrome.log
Firewall Rule (Block Exploit Traffic):
New-NetFirewallRule -DisplayName "Block CefSharp Exploit" -Direction Inbound -Program "C:\Path\chrome.exe" -Action Block
References:
References:
Reported By: https://github.com/advisories/GHSA-f87w-3j5w-v58p
Extra Source Hub:
Undercode
