🛡️ CVE-2021-3695 on Debian — grub2

⚪ Unknown ✅ No Known Exploit OSV

N/A

CVSS Score

0 Low4 Medium7 High9 Critical10

Description

A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.

Distribution advisory

This page covers CVE-2021-3695 as tracked by Debian, for the package grub2. The fix is available in version 2.06-3; earlier versions remain affected.

How this vulnerability can be exploited

This issue can be reached with local access to the system, attack complexity is high, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality low, integrity low, availability low.

Affected software

DEBIAN-CVE-2021-3695 is recorded against 1 package.

grub2 (fixed in 2.06-3)

Timeline and source

Published on 6 July 2022 and last revised on 4 August 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

security-tracker.debian.org (Advisory)

CVE-2021-3695 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Ubuntu

Details

Severity Unknown

CVSS Score N/A

CVSS Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L

CWE N/A

Public Exploit ✅ No

Source OSV

Published 2022-07-06

Updated 2026-08-12

Modified 2026-08-04

Fix URL N/A

Affected Packages

Software	From version	Fixed in
grub2	—	2.06-3

References

ADVISORY https://security-tracker.debian.org/tracker/CVE-2021-3695

🔗 NVD 🔗 Mitre

Similar Threats

Unknown AZL-31685
Unknown AZL-31686
Unknown AZL-27551
Unknown AZL-27552
Unknown AZL-27553

Free Vulnerability Check

Is your site affected by DEBIAN-CVE-2021-3695?

BotEraser helps you identify potentially vulnerable plugins and themes by checking your installation against DEBIAN-CVE-2021-3695 and other known CVE records.

Scan My Site Free →

No credit card required · Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.