CVE-2021-3695: Fedoraproject Fedora

Medium severity, CVSS 4.5. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• Fedoraproject Fedora: version 36 only
• GNU GRUB2: from 2.00, before 2.12 (fixed in 2.12)
• Netapp Ontap Select Deploy Administration Utility: affected versions not specified
• Red Hat Codeready Linux Builder: affected versions not specified
• Red Hat Developer Tools: version 1.0 only
• Red Hat Enterprise Linux: version 8.0 only; version 8.1 only; version 8.4 only; version 9.0 only
• Red Hat Enterprise Linux Eus: version 8.2 only; version 8.4 only; version 8.6 only; version 9.0 only
• Red Hat Enterprise Linux For Power Little Endian: version 8.0 only; version 9.0 only
• Red Hat Enterprise Linux For Power Little Endian Eus: version 8.2 only; version 8.4 only; version 8.6 only; version 9.0 only
• Red Hat Enterprise Linux Server Aus: version 8.2 only; version 8.4 only; version 8.6 only
• Red Hat Enterprise Linux Server For Power Little Endian Update Services For SAP Solutions: version 8.1 only; version 8.2 only; version 8.4 only; version 8.6 only; version 9.0 only
• Red Hat Enterprise Linux Server Tus: version 8.2 only; version 8.4 only; version 8.6 only
• Red Hat Openshift: version 3.0 only
• Red Hat Openshift Container Platform: version 4.6 only; version 4.9 only; version 4.10 only

Published 2022-07-06. Last modified 2026-06-17.