Gigabyte UEFI Firmware Flaws Open Door to Stealthy Bootkits (CVE-2025-7026 / 7027 / 7028 / 7029)
Four critical firmware vulnerabilities in Gigabyte motherboards can bypass Secure Boot and enable stealthy bootkits. Admin privileges alone—not OS-level access—could grant adversaries persistent control. Users must update BIOS immediately or consider hardware replacement for unsupported models.
What’s the Risk?
Security researchers from Binarly and CERT/CC have disclosed four high-severity UEFI firmware vulnerabilities (CVE-2025-7026, 7027, 7028, and 7029) impacting over 240 Gigabyte motherboard models. These flaws reside in the System Management Mode (SMM)—a privileged, pre-OS environment—and can be exploited to bypass Secure Boot and install persistent, nearly undetectable firmware backdoors.
Technical Breakdown
| CVE | Description |
|---|---|
| 7026 / 7029 | Unchecked RBX pointer allows arbitrary write to SMRAM via Thermal/Power config paths. |
| 7028 | Function pointers lack validation—attackers can hijack flash operations like ReadFlash or EraseFlash. |
| 7027 | Double-pointer dereference enables attacker-controlled writes via NVRAM variables. |
An attacker with administrative privileges—either local or remote—can weaponize these flaws to execute code in SMM (Ring -2), bypassing OS-level protections, disabling Secure Boot/BootGuard, and embedding resilient firmware implants.
Affected Platforms & Availability of Patches
- Impacted Systems: Intel-based Gigabyte/AORUS motherboards across H110 through Z590 (including legacy models now at EOL).
- Gigabyte Action: Firmware updates are being released; however, many older boards (especially EOL platforms) may receive no patches at all.
- Disclosure Timeline:
- Reported to CERT/CC in April
- Assigned CVEs in July
- Publicly disclosed mid-July 2025
ThreatGrid Takeaways
- Update Firmware Now – Check Gigabyte’s support site for BIOS/UEFI updates and apply them immediately.
- Verify Security Settings – After patching, ensure Secure Boot remains enabled and functional.
- Segment Access – Restrict administrative access to BIOS/UEFI interfaces, especially for systems with external exposure.
- Monitor for Embedded Implants – Include firmware-level scanning in incident response and forensic workflows.
- Plan for End-of-Life Risks – If hardware is no longer supported, weigh hardware replacement to eliminate persistent security exposure.
