CVE-2024-56732
📋 TL;DR
CVE-2024-56732 is a heap-based buffer overflow vulnerability in HarfBuzz text shaping engine that could allow attackers to execute arbitrary code or cause denial of service. This affects applications using HarfBuzz for text rendering, including web browsers, document viewers, and operating system components. The vulnerability is present in HarfBuzz versions 8.5.0 through 10.0.1.
💻 Affected Systems
- HarfBuzz
- Applications using HarfBuzz library (Chrome, Firefox, LibreOffice, GNOME, KDE, Android, etc.)
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment
Likely Case
Application crash (denial of service) or limited code execution in sandboxed environments
If Mitigated
Application crash with no code execution due to modern exploit mitigations like ASLR and DEP
🎯 Exploit Status
Exploitation requires crafting malicious font/text data and triggering rendering. User interaction needed (opening document/website).
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 10.0.2 and later
Vendor Advisory: https://github.com/harfbuzz/harfbuzz/security/advisories/GHSA-qmp9-xqm5-jh6m
Restart Required: Yes
Instructions:
1. Update HarfBuzz to version 10.0.2 or later. 2. Update dependent applications to use patched library. 3. Restart affected applications/services. 4. For Linux distributions, use package manager: 'sudo apt update && sudo apt upgrade libharfbuzz*' (Debian/Ubuntu) or 'sudo yum update harfbuzz' (RHEL/CentOS).
🔧 Temporary Workarounds
Disable HarfBuzz in applications
allConfigure applications to use alternative text shaping engines if available
Application sandboxing
linuxRun vulnerable applications in sandboxed/containerized environments
firejail --profile=app.profile vulnerable-app
bubblewrap --unshare-all --new-session --die-with-parent vulnerable-app
🧯 If You Can't Patch
- Implement strict input validation for font/text data processing
- Deploy application control/whitelisting to prevent unauthorized code execution
🔍 How to Verify
Check if Vulnerable:
Check HarfBuzz version: 'pkg-config --modversion harfbuzz' or 'ldconfig -p | grep harfbuzz'Check Version:
pkg-config --modversion harfbuzz || harfbuzz --version || dpkg -l | grep harfbuzz || rpm -q harfbuzzVerify Fix Applied:
Verify version is 10.0.2 or later: 'pkg-config --modversion harfbuzz' should return >=10.0.2📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults in harfbuzz-related functions
- Memory corruption errors in application logs
Network Indicators:
- Unusual font file downloads
- Malicious document/website access patterns
SIEM Query:
source="application.logs" AND ("segmentation fault" OR "heap overflow" OR "harfbuzz")