CVE-2021-3695
4.5 · MEDIUMOverview
CVE-2021-3695 is a medium-severity vulnerability affecting gnu grub2. It was published on July 6, 2022 and has a CVSS 3.1 base score of 4.5 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.5, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from gnu. Update grub2 to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| gnu | grub2 | >= 2.00, < 2.12 | Affected |
Frequently Asked Questions
What is CVE-2021-3695?
CVE-2021-3695 is a medium-severity vulnerability affecting gnu grub2. It was published on July 6, 2022 and has a CVSS 3.1 base score of 4.5 (MEDIUM).
How severe is CVE-2021-3695?
This vulnerability has a CVSS 3.1 base score of 4.5, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2021-3695?
Check the references section for vendor advisories and patches from gnu. Update grub2 to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-3695?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-3695 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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