CVE-2026-97631: TianoCore EDK2 (Critical, CVSS 9.5)
- CVSS
- 9.5 Critical (v4.0)
- EPSS
- 0.6% chance of exploitation in the next 30 days (higher than 50.3% of CVEs)
- Exploited in the wild
- Not on CISA’s KEV list
- Public exploit
- Yes, reported in 2 GitHub repositories
- Weakness
- CWE-120, CWE-131, CWE-787
- Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H- Published
- Oct 22, 2026
What it is
EDK2 contains a vulnerability in BIOS where a user may cause “Out-of-bounds Write”, Classic Buffer Overflow, and “Incorrect Calculation of Buffer Size” by remote access. Successful exploitation of this vulnerability can lead to arbitrary code execution. It could also impact Confidentiality, Integrity, and Availability.
Description from the National Vulnerability Database.
What to do
Check whether you run TianoCore EDK2, then apply the vendor’s fix or mitigation from the advisories below. Because this flaw is exploited or has public exploit code, treat it as urgent and check for signs of compromise, not just the patch level.
ThreatRoundup coverage
A 16-Year-Old UEFI Bug Lets One Packet Beat Secure Boot
Sources: NVD, FIRST EPSS, CISA KEV, and public exploit databases (availability only). ThreatRoundup reports whether public exploit code exists but never links to it: fake proof-of-concepts that infect security researchers are common. This page updates automatically.