UEFI flaw: pre-OS code execution

TianoCore EDK2

16-year-old UEFI flaw enables pre-OS code execution, affects servers, and requires firmware patches.

Do this now

No fix yet: limit who can reach it.

Still cooking for EDK2.

First seen: 28 Oct 2026
Last update: 28 Oct 2026, 12:18 UTC
Identifiers: CVE-2026-97631
CVSS: 9.5
Source: news

Check this repository for exposure to one security incident from pwned.coffee. Report first, change nothing until I say so.

## UEFI flaw: pre-OS code execution
Severity: critical. Patch status: no fix yet.
Affected: TianoCore EDK2
Ids: CVE-2026-97631

16-year-old UEFI flaw enables pre-OS code execution, affects servers, and requires firmware patches.

## Steps
1. Search the repo, its CI and infra config for TianoCore EDK2. If present, report the version in use and whether it's affected.
2. EDK2 <= edk2-stable202608: the CVE record names no fix; check the vendor advisory before assuming there is none. Until one ships: restrict network access to it.

## Fix by release line
| Line | State | Fix | Until then |
|---|---|---|---|
| EDK2 <= edk2-stable202608 | not named in the CVE record | check the vendor advisory: https://github.com/tianocore/edk2/security/advisories/GHSA-99cj-7hg9-mp4m | restrict network access to it |

## Report
A table: file, product or package, version in use, affected yes/no, exact fix. Then anything a human has to check outside the repo.

If you have the pwned.coffee MCP server (https://pwned.coffee/mcp), call lookup_cve("CVE-2026-97631") for the latest, and check_repo with this repo's lockfiles, Dockerfiles and workflows for a full receipt.
Sources: https://securityaffairs.com/201928/security/cve-2026-97631-16-year-old-uefi-flaw-threatens-servers.html
https://pwned.coffee/i/uefi-flaw-pre-os-code-execution-cve-2026-97631

Receipt

Exploitation: No known exploitation
Fix by release line: Product Affected Fixed in Source
EDK2 <= edk2-stable202608 fix not named in the CVE record: see vendor advisory CVE record (CNA) checked 28 Oct
The CVE record names no fix for one line; the vendor’s advisory may: github.com
Score: CVSS 9.5 (critical). CVSS 4.0 9.5 (CNA TianoCore) for CVE-2026-97631
Last checked: 28 Oct 2026, 13:19 UTC

Product	Affected	Fixed in	Source
EDK2	<= edk2-stable202608	fix not named in the CVE record: see vendor advisory	CVE record (CNA) checked 28 Oct

Sources: KEV – CVE record ✓ Vendor ✓

Sources

securityaffairs.com: CVE-2026-97631: 16-Year-Old UEFI Flaw Threatens Servers

Wrong fix version, or a source we missed? Send it back to chef@pwned.coffee with the source, and we'll correct it here.

Totalone very hot coffee