Cyber Resilience

CVE-2021-3975

Medium

Published: 23 August 2022

Published
23 August 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0060 69.8th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-3975 is a medium-severity Use After Free (CWE-416) vulnerability in Redhat Enterprise Linux. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 30.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A use-after-free flaw was found in libvirt. The qemuMonitorUnregister() function in qemuProcessHandleMonitorEOF is called using multiple threads without being adequately protected by a monitor lock. This flaw could be triggered by the virConnectGetAllDomainStats API when the guest is shutting down.…

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An unprivileged client with a read-only connection could use this flaw to perform a denial of service attack by causing the libvirt daemon to crash.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

redhat
libvirt
≤ 7.1.0
canonical
ubuntu linux
21.10
fedoraproject
fedora
35
redhat
enterprise linux
8.0
redhat
enterprise linux eus
8.6
redhat
enterprise linux for ibm z systems
8.0
redhat
enterprise linux for ibm z systems eus
8.6
redhat
enterprise linux for power little endian
8.0
redhat
enterprise linux for power little endian eus
8.6
redhat
enterprise linux server for power little endian update services for sap solutions
8.6
+4 more product configuration(s) — see NVD for full list

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References