CVE-2024-38796 Overview
EDK2 contains a vulnerability in the PeCoffLoaderRelocateImage() function. An attacker may cause memory corruption due to a heap-based buffer overflow via an adjacent network. A successful exploit of this vulnerability may lead to a loss of Confidentiality, Integrity, and/or Availability. This vulnerability affects the UEFI firmware development environment and could potentially impact systems utilizing EDK2-based firmware implementations.
Critical Impact
Memory corruption vulnerability in EDK2's PE/COFF image relocation function could allow an adjacent network attacker to compromise system integrity through heap overflow, potentially affecting secure boot processes and firmware-level security.
Affected Products
- EDK2 (TianoCore UEFI firmware development kit)
- Systems using EDK2-based UEFI firmware implementations
- NetApp products using affected EDK2 components
Discovery Timeline
- 2024-09-27 - CVE CVE-2024-38796 published to NVD
- 2025-11-03 - Last updated in NVD database
Technical Details for CVE-2024-38796
Vulnerability Analysis
This vulnerability is classified as CWE-122 (Heap-based Buffer Overflow), affecting the PeCoffLoaderRelocateImage() function within the EDK2 codebase. The function is responsible for processing PE/COFF (Portable Executable/Common Object File Format) images during the UEFI boot process, handling memory relocations necessary for proper image loading.
The overflow condition occurs when processing specially crafted PE/COFF images, allowing an attacker with adjacent network access to trigger memory corruption. Due to the low-level nature of UEFI firmware, successful exploitation could compromise the entire boot chain, potentially bypassing secure boot protections and establishing persistent access at the firmware level.
The attack requires adjacent network access and low privileges, with high attack complexity. While exploitation is not trivial, the potential impact on system integrity is significant given the firmware-level access that could be achieved.
Root Cause
The root cause is a heap-based buffer overflow (CWE-122) in the PeCoffLoaderRelocateImage() function. This function fails to properly validate buffer boundaries when processing relocation entries in PE/COFF images. When an image with malformed or malicious relocation data is processed, the function can write beyond allocated heap buffer boundaries, corrupting adjacent memory regions.
Attack Vector
The attack vector requires adjacent network access, meaning the attacker must be on the same network segment as the target system. This typically involves scenarios where PE/COFF images are loaded from network sources during PXE boot, network-based firmware updates, or similar network boot operations. The attacker would need to intercept or inject a malicious PE/COFF image during the boot process.
The vulnerability is exploited by crafting a PE/COFF image with specially designed relocation entries that trigger the overflow condition when processed by the vulnerable PeCoffLoaderRelocateImage() function. This could allow the attacker to overwrite critical data structures in memory, potentially leading to arbitrary code execution at the firmware level.
Detection Methods for CVE-2024-38796
Indicators of Compromise
- Unexpected firmware integrity check failures or secure boot violations
- Anomalous network traffic during PXE boot or network-based firmware operations
- Corrupted or modified PE/COFF images in firmware update staging areas
- Unusual system behavior immediately following network boot operations
Detection Strategies
- Monitor network boot traffic for unusual or oversized PE/COFF images on the local network segment
- Implement firmware integrity verification using platform attestation mechanisms
- Enable secure boot logging and audit firmware loading events
- Deploy network segmentation to isolate boot infrastructure from untrusted systems
Monitoring Recommendations
- Configure network intrusion detection systems to inspect PXE boot traffic for anomalies
- Enable TPM-based boot measurements to detect firmware tampering
- Review firmware update logs for unauthorized or unexpected update attempts
- Monitor for systems exhibiting boot failures or secure boot policy violations
How to Mitigate CVE-2024-38796
Immediate Actions Required
- Review the GitHub Security Advisory for specific patch information
- Isolate systems using network boot from untrusted network segments
- Verify firmware integrity on systems that may have been exposed
- Apply vendor-specific patches from affected downstream providers
Patch Information
The vulnerability has been addressed by the TianoCore EDK2 maintainers. Organizations should consult the GitHub Security Advisory GHSA-xpcr-7hjq-m6qm for official patch details and version information. Downstream vendors including Debian and NetApp have released advisories addressing this vulnerability:
- Debian LTS Announcement - Debian-specific patch information
- NetApp Security Advisory - NetApp product-specific guidance
Workarounds
- Disable network boot functionality where not required to eliminate the adjacent network attack vector
- Implement strict network segmentation to isolate boot infrastructure from potentially compromised network segments
- Enable secure boot and configure firmware to only load signed, trusted PE/COFF images
- Monitor and restrict access to TFTP/PXE boot servers to authorized systems only
# Example: Disable PXE boot in UEFI configuration (system-specific)
# Consult your system vendor documentation for exact procedures
# 1. Access UEFI/BIOS setup during boot
# 2. Navigate to Boot Options or Network Boot settings
# 3. Disable Network Boot / PXE Boot options
# 4. Enable Secure Boot if not already enabled
# 5. Save configuration and reboot
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
