Privilege escalation in Red Hat Virtualization
| Risk | Low |
| Patch available | YES |
| Number of vulnerabilities | 1 |
| CVE-ID | CVE-2021-22543 |
| CWE-ID | CWE-119 |
| Exploitation vector | Local |
| Public exploit | Public exploit code for vulnerability #1 is available. |
| Vulnerable software |
redhat-virtualization-host (Red Hat package) Operating systems & Components / Operating system package or component redhat-release-virtualization-host (Red Hat package) Operating systems & Components / Operating system package or component Red Hat Virtualization Host Web applications / Remote management & hosting panels Red Hat Virtualization Server applications / Virtualization software |
| Vendor | Red Hat Inc. |
Security Bulletin
This security bulletin contains one low risk vulnerability.
1) Buffer overflow
EUVDB-ID: #VU56018
Risk: Low
CVSSv4.0: 7.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]
CVE-ID: CVE-2021-22543
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: Yes
DescriptionThe vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error in Linux kernel when handling VM_IO|VM_PFNMAP vmas in KVM. A local user can can bypass RO checks and cause the pages to get freed while still accessible by the VMM and guest. As a result, an attacker with the ability to start and control a VM to read/write random pages of memory, can trigger memory corruption and execute arbitrary code with elevated privileges.
Install updates from vendor's website.
redhat-virtualization-host (Red Hat package): 4.3.11-20200922.0.el7_9 - 4.3.18-20210903.0.el7_9
redhat-release-virtualization-host (Red Hat package): 4.3.4-1.el7ev - 4.3.18-1.el7ev
Red Hat Virtualization Host: 4
Red Hat Virtualization: 4
CPE2.3- cpe:2.3:o:red_hat:redhat-virtualization-host_redhat_package:4.3.11-20200922.0.el7_9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:redhat-virtualization-host_redhat_package:4.3.12-20201216.0.el7_9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:redhat-virtualization-host_redhat_package:4.3.13-20210127.0.el7_9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:redhat-release-virtualization-host_redhat_package:4.3.4-1.el7ev:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:redhat-release-virtualization-host_redhat_package:4.3.5-2.el7ev:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:redhat-release-virtualization-host_redhat_package:4.3.5-4.el7ev:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:a:red_hat:red_hat_virtualization_host:4:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:red_hat_virtualization:4:*:*:*:*:*:*:*
https://access.redhat.com/errata/RHSA-2021:3943
Q & A
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.
