Use After Free in Linux Kernel

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 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.

Vulnerability class: Use-After-Free

EPSS: 0.004 (36.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-20226?
CVE-2021-20226 is a high-severity vulnerability in Linux Kernel, classified under Use After Free. CVSS score: 7.8/10. Published 2021-02-23.
How severe is CVE-2021-20226?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-20226 known to be exploited?
21 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.