CVE-2021-20181

A race condition flaw was found in the 9pfs server implementation of QEMU up to and including 5.2.0. This flaw allows a malicious 9p client to cause a use-after-free error, potentially escalating their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity as well as system availability.

CVSS v3 7.5 HIGH
CVSS v2.0 6.9 MEDIUM

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 0.8 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

6.9^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:M/Au:N/C:C/I:C/A:C

Exploitability : 3.4 / Impact : 10.0

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1927007	Issue Tracking Patch Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00024.html	Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html	Mailing List Third Party Advisory
https://security.netapp.com/advisory/ntap-20210720-0009/	Third Party Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-159/	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:debian:debian_linux:9.0:::::::*
	cpe:2.3:o:debian:debian_linux:10.0:::::::*

History

No history.

Information

Published : 2021-05-13 16:15

Updated : 2023-11-07 03:28

NVD link : CVE-2021-20181

Mitre link : CVE-2021-20181

CVE.ORG link : CVE-2021-20181

JSON object : View

Products Affected

debian

debian_linux

qemu

qemu

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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