cvedb.io
CVE-2021-47451
HIGH · CVSS 7.8
EPSS exploitation probability: 0%
Published 2024-05-22T07:15:10.220 · Last modified 2026-08-04T10:17:04.087

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbage value Currently, when the rule related to IDLETIMER is added, idletimer_tg timer structure is initialized by kmalloc on executing idletimer_tg_create function. However, in this process timer->timer_type is not defined to a specific value. Thus, timer->timer_type has garbage value and it occurs kernel panic. So, this commit fixes the panic by initializing timer->timer_type using kzalloc instead of kmalloc. Test commands: # iptables -A OUTPUT -j IDLETIMER --timeout 1 --label test $ cat /sys/class/xt_idletimer/timers/test Killed Splat looks like: BUG: KASAN: user-memory-access in alarm_expires_remaining+0x49/0x70 Read of size

Affected products

linux — linux_kernel

Does this affect you?

Add your gear to cvedb and we'll alert you only when linux ships something exploited.

Check my exposure →

References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.