High severity · published Feb 23, 2021
CVE-2021-20226
A use-after-free flaw was found in the io_uring in Linux kernel, where a local attacker with a user privilege could cause a denial of service problem on the system The issue…
7.8
CVSS
0.4%
EPSS
No
On KEV
Description
A use-after-free flaw was found in the io_uring in Linux kernel, where a local attacker with a user privilege could cause a denial of service problem on the system The issue results from the lack of validating the existence of an object prior to performing operations on the object by not incrementing the file reference counter while in use. The highest threat from this vulnerability is to data integrity, confidentiality and system availability.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
5.5 before 5.8.18; 5.9.0 before 5.9.3 · source: NVD
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20226
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20226
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1873476
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210401-0001/
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