{"id":"CVE-2026-97631","title":"Pre-boot RCE in EDK II PXE driver","summary":"EDK2 contains a vulnerability in BIOS where a user may cause “Out-of-bounds\nWrite”, Classic\nBuffer Overflow, and “Incorrect Calculation of Buffer Size” by remote access. Successful exploitation of this vulnerability\ncan lead to arbitrary…","severity":"critical","cvss":9.5,"cvssVector":"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","cvssSource":"cna","cwe":["CWE-120","CWE-131","CWE-787"],"vendor":"TianoCore","product":"NetworkPkg","affected":["NetworkPkg <= edk2-stable202608"],"published":"2026-10-22","updated":"2026-10-28","sourceUpdated":"2026-10-28T16:06:34.929Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-97631","references":[{"url":"https://github.com/tianocore/edk2/security/advisories/GHSA-99cj-7hg9-mp4m"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97631.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-97631"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2559129"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97631"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97631"}],"tags":["cve.org","csaf","vex","red-hat"],"epss":0.00483,"epssPercentile":0.41529,"scores":{"cna":9.5,"vendor":8.8},"ingestedAt":"2026-10-22T22:00:50.345Z","slug":"CVE-2026-97631","body":"## Overview\n\nEDK2 contains a vulnerability in BIOS where a user may cause “Out-of-bounds\nWrite”, Classic\nBuffer Overflow, and “Incorrect Calculation of Buffer Size” by remote access. Successful exploitation of this vulnerability\ncan lead to arbitrary\ncode execution. It could also impact\nConfidentiality,\nIntegrity,\nand Availability.\n\n## Affected\n\n- `NetworkPkg <= edk2-stable202608`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Critical · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97631.json)","depth":"midnight","depthScore":52,"depthScoreParts":{"impact":52.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":230688,"id":"CVE-2026-97631","ts":1793200418052,"field":"cvss","old":"8.8","new":"9.5"},{"seq":230687,"id":"CVE-2026-97631","ts":1793200418052,"field":"severity","old":"high","new":"critical"},{"seq":228728,"id":"CVE-2026-97631","ts":1792844938576,"field":"cvss","old":"9.5","new":"8.8"},{"seq":228727,"id":"CVE-2026-97631","ts":1792844938576,"field":"severity","old":"critical","new":"high"}]}