Use After Free in Gnu Grub2
CVE-2022-28736
There's a use-after-free vulnerability in grub_cmd_chainloader() function; The chainloader command is used to boot up operating systems that doesn't support multiboot and do not have direct support from GRUB2. When executing chainloader more than once a use-after-free vulnerability is triggered. If an attacker can control the GRUB2's memory allocation pattern sensitive data may be exposed and arbitrary code execution can be achieved.
Vulnerability class: Use-After-Free
EPSS: 0.003 (21.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Gnu Grub2
- Gnu Project Grub — versions 0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@ubuntu.com (mailing-list, Mailing List, Third Party Advisory)
- security@ubuntu.com (issue-tracking, Third Party Advisory)
- security@ubuntu.com
Frequently asked questions
- What is CVE-2022-28736?
- CVE-2022-28736 is a medium-severity vulnerability in Gnu Grub2, classified under Use After Free. CVSS score: 6.4/10. Published 2023-07-20.
- How severe is CVE-2022-28736?
- Medium severity. CVSS v3 base score is 6.4 out of 10.
- Is CVE-2022-28736 known to be exploited?
- 18 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.