CVE-2021-47289: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: ACPI: fix NULL pointer dereference Commit 71f642833284 ("ACPI: utils: Fix reference counting in for_each_acpi_dev_match()") started doing "acpi_dev_put()" on a pointer that was possibly NULL. That fails miserably, because that helper inline function is not set up to handle that case. Just make acpi_dev_put() silently accept a NULL pointer, rather than calling down to put_device() with an invalid offset off that NULL pointer.

Affected products

• Linux Linux Kernel: before 5.4.139 (fixed in 5.4.139); from 5.5, before 5.10.57 (fixed in 5.10.57); from 5.11, before 5.13.6 (fixed in 5.13.6); version 5.14 only

Published 2024-05-21. Last modified 2026-06-17.