CVE-2021-20233

Related Vulnerabilities: CVE-2021-20233  

A flaw was found in grub2. Setparam_prefix() in the menu rendering code performs a length calculation on the assumption that expressing a quoted single quote will require 3 characters, while it actually requires 4 characters which allows an attacker to corrupt memory by one byte for each quote in the input. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Description

A flaw was found in grub2. Setparam_prefix() in the menu rendering code performs a length calculation on the assumption that expressing a quoted single quote will require 3 characters, while it actually requires 4 characters which allows an attacker to corrupt memory by one byte for each quote in the input. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Additional Information

  • Bugzilla 1926263: CVE-2021-20233 grub2: Heap out-of-bounds write due to miscalculation of space required for quoting
  • CWE-787: Out-of-bounds Write
  • FAQ: Frequently asked questions about CVE-2021-20233