Pre-boot RCE in EDK II PXE driver (TianoCore EDK2)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.64 % · percentile 50 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- TianoCore
- NVD status
- Deferred
Description
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.
Weaknesses (CWE)
- CWE-120 — Buffer Copy without Checking Size of Input
- CWE-131 — Incorrect Calculation of Buffer Size
- CWE-787 — Out-of-bounds Write
References
- https://github.com/tianocore/edk2/security/advisories/GHSA-99cj-7hg9-mp4m
- https://arstechnica.com/security/2026/10/code-execution-flaw-in-uefi-firmware-threatens-most-servers-on-planet-earth/
- https://news.ycombinator.com/item?id=50265393
- https://github.com/microsoft/mu_basecore/pull/1990
- https://github.com/microsoft/mu_basecore/pull/1989
- http://www.openwall.com/lists/oss-security/2026/10/28/4
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | CRITICAL 9.5 | 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 | TianoCore |
| CVSS 4.0 | CRITICAL 9.5 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD · infosec@edk2.groups.io (Secondary) |
European references
- ENISA EUVD · EUVD-2026-108230
- GCVE · GCVE-0-2026-97631
Affected products
| Product | Versions |
|---|---|
| TianoCore · EDK2 | affected 0 ≤ edk2-stable202608 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |