Use After Free in Linux Linux_kernel

CVE-2021-4203

A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privileges may crash the system…

Vulnerability class: Race Condition

EPSS: 0.018 (75.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-4203?
CVE-2021-4203 is a medium-severity vulnerability in Linux Linux_kernel, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 6.8/10. Published 2022-03-25.
How severe is CVE-2021-4203?
Medium severity. CVSS v3 base score is 6.8 out of 10.
Is CVE-2021-4203 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.