CVE-2024-21924
📋 TL;DR
This vulnerability allows a ring 0 attacker to exploit an SMM callout in the AmdPlatformRasSspSmm driver to modify boot services handlers, potentially leading to arbitrary code execution. It affects systems with AMD processors that use this specific driver. Attackers would need local administrative privileges to exploit this vulnerability.
💻 Affected Systems
- AMD Ryzen processors
- AMD EPYC processors
- AMD Threadripper processors
⚠️ 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
Complete system compromise with persistent malware installation below the operating system level, allowing attackers to bypass all security controls and maintain persistence across reboots.
Likely Case
Privilege escalation from ring 0 to SMM (System Management Mode) allowing attackers to execute arbitrary code with highest system privileges and potentially install rootkits.
If Mitigated
Limited impact if proper privilege separation and SMM protections are in place, though the vulnerability still provides a significant attack surface.
🎯 Exploit Status
Exploitation requires local administrative privileges and knowledge of SMM exploitation techniques. No public exploits are currently available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware updates as specified in AMD advisory SB-7028
Vendor Advisory: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7028.html
Restart Required: Yes
Instructions:
1. Check your system manufacturer's website for BIOS/UEFI firmware updates. 2. Download the appropriate firmware update for your specific system model. 3. Follow manufacturer instructions to update firmware. 4. Reboot system to apply changes.
🔧 Temporary Workarounds
Restrict administrative access
allLimit the number of users with local administrative privileges to reduce attack surface.
Enable SMM protection features
allEnable SMM protection features in BIOS/UEFI settings if available.
🧯 If You Can't Patch
- Implement strict access controls to limit administrative privileges
- Monitor for suspicious SMM-related activity and privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check system firmware version against AMD's advisory SB-7028 or use manufacturer's vulnerability checking tools.Check Version:
wmic bios get smbiosbiosversion (Windows) or dmidecode -s bios-version (Linux)Verify Fix Applied:
Verify firmware version has been updated to a version not listed in the AMD advisory.📡 Detection & Monitoring
Log Indicators:
- Unexpected SMM handler modifications
- Suspicious firmware access attempts
- Privilege escalation attempts from ring 0
Network Indicators:
- None - this is a local privilege escalation vulnerability
SIEM Query:
Search for events indicating firmware modification attempts or SMM-related anomalies