VDB-207072 · CVE-2021-3975 · Nessus 209569

libvirt virConnectGetAllDomainStats API qemuMonitorUnregister use after free

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4.9	$0-$5k	0.00

Summaryinfo

A vulnerability described as problematic has been identified in libvirt. This affects the function qemuMonitorUnregister of the component virConnectGetAllDomainStats API. The manipulation results in use after free. This vulnerability is reported as CVE-2021-3975. No exploit exists. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability classified as problematic has been found in libvirt (Virtualization Software) (unknown version). Affected is the function qemuMonitorUnregister of the component virConnectGetAllDomainStats API. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on availability. CVE summarizes:

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. 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.

The weakness was disclosed 08/24/2022 as 1ac703a7d0789e46833f4013a3876c2e3af18ec7. The advisory is shared for download at github.com. This vulnerability is traded as CVE-2021-3975 since 11/18/2021. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 209569 (Oracle Linux 8 : virt:kvm_utils1 (ELSA-2024-12791)), which helps to determine the existence of the flaw in a target environment.

Applying the patch 1ac703a7d0789e46833f4013a3876c2e3af18ec7 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at Tenable (209569). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Virtualization Software

Name

libvirt

License

open-source

Website

Product: https://github.com/libvirt/libvirt/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.9

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 209569
Nessus Name: Oracle Linux 8 : virt:kvm_utils1 (ELSA-2024-12791)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: 1ac703a7d0789e46833f4013a3876c2e3af18ec7

Timelineinfo

11/18/2021 🔍
08/24/2022 +278 days 🔍
08/24/2022 +0 days 🔍
10/26/2024 +794 days 🔍

Sourcesinfo

Product: github.com

Advisory: 1ac703a7d0789e46833f4013a3876c2e3af18ec7
Status: Confirmed

CVE: CVE-2021-3975 (🔍)
GCVE (CVE): GCVE-0-2021-3975
GCVE (VulDB): GCVE-100-207072

Entryinfo

Created: 08/24/2022 09:35
Updated: 10/26/2024 22:38
Changes: 08/24/2022 09:35 (42), 09/25/2022 09:56 (11), 10/26/2024 22:38 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.