Security readout for executives and security teams
Plain-English summary
CVE-2023-4693 is a GRUB2 bootloader flaw in NTFS filesystem parsing. A physically present attacker with high privileges could use a crafted NTFS image to read sensitive memory, such as cached secrets or EFI variable values. The impact is confidentiality-focused, not code execution or service disruption in the supplied sources.
Executive priority
Treat this as a moderate-priority infrastructure hardening issue. It is not reported as actively exploited in the supplied sources, but it can leak sensitive pre-boot memory when physical or privileged local access is possible. Prioritize high-sensitivity endpoints and shared-access environments.
Technical view
The issue is a CWE-125 out-of-bounds read in GRUB2 fs/ntfs.c. The CVSS 3.1 vector is local, high complexity, high privileges required, no user interaction, changed scope, high confidentiality impact, and no integrity or availability impact. Red Hat lists grub2 on RHEL 7, 8, and 9 as affected.
Likely exposure
Exposure is most relevant on systems that boot with GRUB2 and may parse attacker-controlled NTFS media or images before the operating system loads. The supplied affected list names Red Hat Enterprise Linux 7, 8, and 9 grub2 packages; other distributions should be checked against their own advisories.
Exploitation context
The source bundle does not indicate active exploitation, and KEV is false. Practical abuse appears constrained by physical/local access, high privileges, and high attack complexity. The business risk is highest for sensitive endpoints, shared systems, kiosks, labs, and environments where boot media control is weak.
Researcher notes
Avoid assuming remote exploitation or code execution. The strongest supported impact is memory disclosure through GRUB2 NTFS parsing. The bundle names affected Red Hat products but does not include complete fixed-version details, so validation should reference the vendor advisories directly.
Mitigation direction
- Apply relevant GRUB2 updates from vendor advisories, including Red Hat RHSA-2024:2456 and RHSA-2024:3184.
- Check distribution-specific guidance for Debian, Fedora, Gentoo, NetApp, or other GRUB2 consumers.
- Restrict physical access and boot-from-external-media paths on sensitive systems.
- Review secure boot and firmware boot-order controls where operationally appropriate.
Validation and detection
- Inventory systems using GRUB2, prioritizing RHEL 7, 8, and 9 assets.
- Check installed grub2 package versions against vendor advisory status.
- Confirm whether systems can boot or parse untrusted NTFS media during startup.
- Verify remediation through approved package management and change records.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-125: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2023-4693 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N0.84redhatVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Reported to Red Hat.
- Source timelineredhat
Made public.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2024:2456CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:3184CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2023-4693CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2238343CVE reference, redhat · issue-tracking, x_refsource_REDHAT
- https://dfir.ru/2023/10/03/cve-2023-4692-cve-2023-4693-vulnerabilities-in-the-grub-boot-manager/CVE reference, redhat
- https://lists.gnu.org/archive/html/grub-devel/2023-10/msg00028.htmlCVE reference, redhat
- https://seclists.org/oss-sec/2023/q4/37CVE reference, redhat
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FUU42E7CPYLATXOYVYNW6YTXXULAOV6L/CVE reference, CVE · x_transferred
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OIRJ5UZRXX2KLR4IKBJEQUNGOCXMMDLY/CVE reference, CVE · x_transferred
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PERFILCHFEUGG3OAMC6W55P6DDIBZK4Q/CVE reference, CVE · x_transferred
- https://security.gentoo.org/glsa/202311-14CVE reference, CVE · x_transferred
- https://security.netapp.com/advisory/ntap-20231208-0002/CVE reference, CVE · x_transferred
- https://lists.debian.org/debian-lts-announce/2023/10/msg00007.htmlCVE reference, CVE
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.