CVE-2021-47248: Linux Kernel

Medium severity, CVSS 4.7. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: udp: fix race between close() and udp_abort() Kaustubh reported and diagnosed a panic in udp_lib_lookup(). The root cause is udp_abort() racing with close(). Both racing functions acquire the socket lock, but udp{v6}_destroy_sock() release it before performing destructive actions. We can't easily extend the socket lock scope to avoid the race, instead use the SOCK_DEAD flag to prevent udp_abort from doing any action when the critical race happens. Diagnosed-and-tested-by: Kaustubh Pandey <kapandey@codeaurora.org>

Affected products

• Linux Linux Kernel: from 4.9, before 4.9.274 (fixed in 4.9.274); from 4.10, before 4.14.238 (fixed in 4.14.238); from 4.15, before 4.19.196 (fixed in 4.19.196); from 4.20, before 5.4.128 (fixed in 5.4.128); from 5.5, before 5.10.46 (fixed in 5.10.46); from 5.11, before 5.12.13 (fixed in 5.12.13); …

Published 2024-05-21. Last modified 2026-08-04.