Vulnerability Details : CVE-2021-4032
Potential exploit
A vulnerability was found in the Linux kernel's KVM subsystem in arch/x86/kvm/lapic.c kvm_free_lapic when a failure allocation was detected. In this flaw the KVM subsystem may crash the kernel due to mishandling of memory errors that happens during VCPU construction, which allows an attacker with special user privilege to cause a denial of service. This flaw affects kernel versions prior to 5.15 rc7.
Vulnerability category: Denial of service
Products affected by CVE-2021-4032
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:-:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*
Exploit prediction scoring system (EPSS) score for CVE-2021-4032
0.09%
Probability of exploitation activity in the next 30 days
EPSS Score History
~ 41 %
Percentile, the proportion of vulnerabilities that are scored at or less
CVSS scores for CVE-2021-4032
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source | First Seen |
---|---|---|---|---|---|---|
4.9
|
MEDIUM | AV:L/AC:L/Au:N/C:N/I:N/A:C |
3.9
|
6.9
|
NIST | |
4.4
|
MEDIUM | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H |
0.8
|
3.6
|
NIST |
CWE ids for CVE-2021-4032
-
The product does not properly "clean up" and remove temporary or supporting resources after they have been used.Assigned by:
- nvd@nist.gov (Primary)
- secalert@redhat.com (Secondary)
References for CVE-2021-4032
-
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f7d8a19f9a056a05c5c509fa65af472a322abfee
kernel/git/torvalds/linux.git - Linux kernel source treeExploit;Patch;Third Party Advisory
-
https://bugzilla.redhat.com/show_bug.cgi?id=2027403
2027403 – (CVE-2021-4032) CVE-2021-4032 kernel: kvm: mishandling of memory error during VCPU construction can lead to DoSIssue Tracking;Patch;Third Party Advisory
-
https://lkml.org/lkml/2021/9/8/587
LKML: Steven Rostedt: Re: WARNING in __static_key_slow_dec_deferredExploit;Third Party Advisory
Jump to