CVE-2021-47073: linux kernel vulnerability

What is known

In the Linux kernel, the following vulnerability has been resolved: platform/x86: dell-smbios-wmi: Fix oops on rmmod dell_smbios init_dell_smbios_wmi() only registers the dell_smbios_wmi_driver on systems where the Dell WMI interface is supported. While exit_dell_smbios_wmi() unregisters it unconditionally, this leads to the following oops: [ 175.722921] ------------[ cut here ]------------ [ 175.722925] Unexpected driver unregister! [ 175.722939] WARNING: CPU: 1 PID: 3630 at drivers/base/driver.c:194 driver_unregister+0x38/0x40 ... [ 175.723089] Call Trace: [ 175.723094] cleanup_module+0x5/0xedd [dell_smbios] ... [ 175.723148] ---[ end trace 064c34e1ad49509d ]--- Make the unregister happen on the same condition the register happens to fix this.

Business impact

Successful exploitation of CVE-2021-47073, a medium vulnerability (CVSS 5.5) affecting linux kernel, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether linux kernel is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

• NVD
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