Physical memory disclosure via unchecked resident NTFS attribute
Published Oct 25, 2023 · Updated Jul 21, 2026
Out-of-bounds read in the GRUB2 NTFS driver on Red Hat Enterprise Linux allows physically proximate attackers to disclose memory. The read_data function trusts resident $DATA attribute length and offset fields, then copies from the MFT buffer without proving the source range remains inside that buffer. Physical access is required to supply a crafted NTFS filesystem image; successful exploitation exposes cached secrets or EFI variable values without modifying data.
Summary
What happened
Out-of-bounds read in the GRUB2 NTFS driver on Red Hat Enterprise Linux allows physically proximate attackers to disclose memory. The read_data function trusts resident $DATA attribute length and offset fields, then copies from the MFT buffer without proving the source range remains inside that buffer. Physical access is required to supply a crafted NTFS filesystem image; successful exploitation exposes cached secrets or EFI variable values without modifying data.
The record
- CVE
- CVE-2023-4693
- Published
- Oct 25, 2023
- Updated
- Jul 21, 2026
- Vendor
- Red Hat
- Product
- Red Hat Enterprise Linux 8
- Classifications
- CWE-125, T1005
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 25, 2023CVE publishedPublication date reported by the CVE source.
- Jul 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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