CVE-2021-47533: linux kernel vulnerability

CVE-2021-47533: high vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2021-47533CVSS 7.8Linux

CVE-2021-47533: linux kernel vulnerability

CVE-2021-47533: high vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
7.8 HIGH
EPSS
12.24%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: drm/vc4: kms: Clear the HVS FIFO commit pointer once done Commit 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") introduced a wait on the previous commit done on a given HVS FIFO. However, we never cleared that pointer once done. Since drm_crtc_commit_put can free the drm_crtc_commit structure directly if we were the last user, this means that it can lead to a use-after free if we were to duplicate the state, and that stale pointer would even be copied to the new state. Set the pointer to NULL once we're done with the wait so that we don't carry over a pointer to a free'd structure.

Business impact

Successful exploitation of CVE-2021-47533, a high vulnerability (CVSS 7.8) 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

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