CVE-2025-45663
📋 TL;DR
CVE-2025-45663 is a memory corruption vulnerability in NetSurf browser v3.11 where uninitialized heap memory is read when creating DOM event structures. This could allow attackers to leak sensitive information or potentially execute arbitrary code. Users running NetSurf v3.11 are affected.
💻 Affected Systems
- NetSurf
📦 What is this software?
Netsurf by Netsurf Browser
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure leading to memory content leakage, potentially including sensitive data like passwords, session tokens, or other application memory contents.
Likely Case
Application crash or information disclosure of random memory contents, potentially revealing internal state information.
If Mitigated
Limited impact with proper memory isolation and ASLR protections, possibly just application instability.
🎯 Exploit Status
Exploitation requires user to visit malicious website. Public disclosure includes technical details that could facilitate exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v3.12 or later
Vendor Advisory: https://www.netsurf-browser.org/news/releases/
Restart Required: Yes
Instructions:
1. Visit netsurf-browser.org 2. Download latest version 3. Install over existing installation 4. Restart browser
🔧 Temporary Workarounds
Disable JavaScript
allPrevents exploitation by disabling JavaScript execution which is typically required for DOM event manipulation.
Not applicable - configure via browser settings
🧯 If You Can't Patch
- Restrict browser usage to trusted websites only
- Implement application whitelisting to prevent NetSurf execution
🔍 How to Verify
Check if Vulnerable:
Check NetSurf version via Help → About or 'netsurf --version' commandCheck Version:
netsurf --versionVerify Fix Applied:
Verify version is v3.12 or later and test with known safe websites📡 Detection & Monitoring
Log Indicators:
- Application crashes
- Memory access violation errors
- Unexpected browser termination
Network Indicators:
- Connections to suspicious domains followed by browser crashes
SIEM Query:
process_name:"netsurf" AND (event_type:"crash" OR error_code:"ACCESS_VIOLATION")