CVE-2021-3697: gnu grub2 Out-of-bounds Write
Vulnerability summary
CVE-2021-3697 is a high (CVSS 7.0) Out-of-bounds Write vulnerability in gnu grub2. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.2% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 16 · Related 11Timeline
- 06-07-2022PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated7.0HighCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated7.0HighCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.0HighCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.46%
Chance of exploitation in the next 30 days
Percentile
38%
Versus all other CVEs
30-day change
0.00 pp
From 0.46% 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
Redhat11 products
- codeready_linux_builderna
- developer_tools1.0
- enterprise_linux8.0 | 8.1 | 8.4 | 9.0
- enterprise_linux_eus8.2 | 8.4 | 8.6 | 9.0
- enterprise_linux_for_power_little_endian8.0 | 9.0
Ubuntu2 products
- grub2-signedAll versions (No fix recorded) | < 1.187.3~18.04.1 | < 1.187.3~20.04.1 | < 1.187.3~22.04.1
- grub2-unsignedAll versions (No fix recorded) | < 2.06-2ubuntu14.1
Alpine1 product
- grub< 2.06-r3 | < 2.06-r8 | < 2.06-r12 | < 2.06-r13
Debian1 product
- grub2< 2.06-3
Gnu1 product
- grub2≥ 2.00, < 2.12
5 vendors · 16 products
