High severity · published May 13, 2021
CVE-2021-20181
A race condition flaw was found in the 9pfs server implementation of QEMU up to and including 5.2.0
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
QE
Qemu · Qemu
through 5.2.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20181
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20181
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1927007
Mailing List
https://lists.debian.org/debian-lts-announce/2021/02/msg00024.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210720-0009/
Third Party Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-159/
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