CVE-2025-0690: grub2 Out-of-bounds Write
Vulnerability summary
CVE-2025-0690 is a medium (CVSS 6.1) Out-of-bounds Write vulnerability in grub2. EPSS estimates a 0.72% chance of exploitation in the next 30 days, higher than 52.8% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 10 · Related 9Timeline
- 24-02-2025PublishedVulnerability first disclosed.
- 08-07-2026Last modifiedVulnerability information updated.
Description
The read command is used to read the keyboard input from the user, while reads it keeps the input length in a 32-bit integer value which is further used to reallocate the line buffer to accept the next character. During this process, with a line big enough it's possible to make this variable to overflow leading to a out-of-bounds write in the heap based buffer. This flaw may be leveraged to corrupt grub's internal critical data and secure boot bypass is not discarded as consequence.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
- NVDNIST6.1MediumCVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.72%
Chance of exploitation in the next 30 days
Percentile
53%
Versus all other CVEs
30-day change
+0.01 pp
From 0.70% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu3 products
- grub2All versions (No fix recorded)
- grub2-signedAll versions (No fix recorded)
- grub2-unsignedAll versions (No fix recorded)
Debian1 product
- grub2< 2.06-13+deb12u2 | < 2.12-6
2 vendors · 4 products
