CVE-2021-31728
Incorrect access control in zam64.sys, zam32.sys in MalwareFox AntiMalware 2.74.0.150 allows a non-privileged process to open a handle to...
- Published
- May 17, 2021
- Updated
- Aug 3, 2024
- Assigning CNA
- mitre
- Evidence observed
- Aug 8, 2026
Primary CVSS
nvd · CVSS 3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLow · next 30 days
- Percentile
- 88.3%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
Summary
Incorrect access control in zam64.sys, zam32.sys in MalwareFox AntiMalware 2.74.0.150 allows a non-privileged process to open a handle to \.\ZemanaAntiMalware, register itself with the driver by sending IOCTL 0x80002010, allocate executable memory using a flaw in IOCTL 0x80002040, install a hook with IOCTL 0x80002044 and execute the executable memory using this hook with IOCTL 0x80002014 or 0x80002018, this exposes ring 0 code execution in the context of the driver allowing the non-privileged process to elevate privileges.
Sources
1Public proof-of-concept for CVE-2021-31727 and CVE-2021-31728 demonstrating unrestricted disk read/write and arbitrary ring 0 code execution in zam64.sys and zam32.sys drivers.
Responsible use
Use vulnerability information only on systems you own or are authorized to test. Kitploit links to public research metadata and does not store exploit code or malicious payloads.