VULNERABILITY INTELLIGENCE

CVE-2021-3695

CVSS score4.5 MEDIUM
EPSS probability0.46%
CISA KEVNot currently listed
Published2022-07-06
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L

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.

Weakness classification

  • secalert@redhat.com: CWE-787
  • nvd@nist.gov: CWE-787

Primary references