Buffer overflow in edk2 - CVE-2026-97631
Published: November 4, 2026
Vulnerability identifier: #VU159000
CSH Severity: High
CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-97631
CWE-ID: CWE-120
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error in BIOS when the affected machine is PXE-booting over IPv4 or IPv6. A remote attacker can use specially crafted ICMP error messages, trigger memory corruption and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
edk2
How to mitigate CVE-2026-97631
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.
External References
- https://github.com/tianocore/edk2/security/advisories/GHSA-99cj-7hg9-mp4m
- http://www.openwall.com/lists/oss-security/2026/10/28/4
- https://arstechnica.com/security/2026/10/code-execution-flaw-in-uefi-firmware-threatens-most-servers-on-planet-earth/
- https://github.com/microsoft/mu_basecore/pull/1989
- https://github.com/microsoft/mu_basecore/pull/1990
- https://news.ycombinator.com/item?id=50265393