CVE-2023-4693: gnu grub2 Out-of-bounds Read
Vulnerability summary
CVE-2023-4693 is a medium (CVSS 5.3) Out-of-bounds Read vulnerability in gnu grub2. EPSS estimates a 0.49% chance of exploitation in the next 30 days, higher than 40.6% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 12 · Related 7Timeline
- 25-10-2023PublishedVulnerability first disclosed.
- 21-07-2026Last modifiedVulnerability information updated.
Description
An out-of-bounds read flaw was found on grub2's NTFS filesystem driver. This issue may allow a physically present attacker to present a specially crafted NTFS file system image to read arbitrary memory locations. A successful attack allows sensitive data cached in memory or EFI variable values to be leaked, presenting a high Confidentiality risk.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated4.6MediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NDiffers
- OSV · DebianEcosystem advisory · calculated4.6MediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NDiffers
- NVDNIST4.6MediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NDiffers
EPSS trend
Probability
0.49%
Chance of exploitation in the next 30 days
Percentile
41%
Versus all other CVEs
30-day change
-0.01 pp
From 0.50% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (dfir.ru)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Ubuntu2 products
- grub2-signedAll versions (No fix recorded) | < 1.187.6~20.04.1 | < 1.187.6 | < 1.199
- grub2-unsignedAll versions (No fix recorded) | < 2.06-2ubuntu14.4
Debian1 product
- grub2< 2.06-13+deb12u1 | < 2.12~rc1-11
Gnu1 product
- grub2< 2.12
Redhat1 product
- enterprise_linux8.0 | 9.0
4 vendors · 5 products
References
18 links- dfir.ru/2023/10/03/cve-2023-4692-cve-2023-4693-vulnerabilities-in-the-grub-boot-manager/REPORTExploitThird Party Advisory
- lists.fedoraproject.org/archives/…X Transferred
- lists.fedoraproject.org/archives/…X Transferred
- lists.fedoraproject.org/archives/…X Transferred
Show all 18 references
- security.gentoo.org/glsa/202311-14X Transferred
- security.netapp.com/advisory/ntap-20231208-0002/X Transferred
