# CVE-2023-4692: Grub2: out-of-bounds write at fs/ntfs.c may lead to unsigned code execution

Status: published. Published: 2023-10-25. Updated: 2026-11-07.

An out-of-bounds write flaw was found in grub2's NTFS filesystem driver. This issue may allow an attacker to present a specially crafted NTFS filesystem image, leading to grub's heap metadata corruption. In some circumstances, the attack may also corrupt the UEFI firmware heap metadata. As a result, arbitrary code execution and secure boot protection bypass may be achieved.

## Remediation

No remediation reported in collected sources

## Affected products and versions

-  /  (grub): ≥ 2.12; < * (unaffected, custom). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (grub2): ≥ 1:2.02-156.el8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (grub2): ≥ 1:2.06-77.el9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (grub2): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.54% as of 2026-11-06; percentile 45.60%

- SSVC: exploitation poc; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-122

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2024:2456 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3184 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-4692 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2236613 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://dfir.ru/2023/10/03/cve-2023-4692-cve-2023-4693-vulnerabilities-in-the-grub-boot-manager/ (CNA: redhat)

- https://lists.gnu.org/archive/html/grub-devel/2023-10/msg00028.html (CNA: redhat)

- https://seclists.org/oss-sec/2023/q4/37 (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2024:2456 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3184 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-4692 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2236613 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://dfir.ru/2023/10/03/cve-2023-4692-cve-2023-4693-vulnerabilities-in-the-grub-boot-manager/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FUU42E7CPYLATXOYVYNW6YTXXULAOV6L/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OIRJ5UZRXX2KLR4IKBJEQUNGOCXMMDLY/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PERFILCHFEUGG3OAMC6W55P6DDIBZK4Q/ (ADP: CVE; x_transferred)

- https://lists.gnu.org/archive/html/grub-devel/2023-10/msg00028.html (ADP: CVE; x_transferred)

- https://seclists.org/oss-sec/2023/q4/37 (ADP: CVE; x_transferred)

- https://security.gentoo.org/glsa/202311-14 (ADP: CVE; x_transferred)

- https://security.netapp.com/advisory/ntap-20231208-0002/ (ADP: CVE; x_transferred)

- https://lists.debian.org/debian-lts-announce/2023/10/msg00007.html (ADP: CVE)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-4692; retrieved 2026-11-07; source updated 2026-11-07

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-4692; retrieved 2026-11-07; source updated Not reported

Revision: 53a93d3e0e9b49ad936a888d7e1ab33e57208256f44941d7867b32592dde0225

Canonical: https://y2.dev/cve/CVE-2023-4692

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