CVE-2021-47046: linux kernel vulnerability

What is known

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix off by one in hdmi_14_process_transaction() The hdcp_i2c_offsets[] array did not have an entry for HDCP_MESSAGE_ID_WRITE_CONTENT_STREAM_TYPE so it led to an off by one read overflow. I added an entry and copied the 0x0 value for the offset from similar code in drivers/gpu/drm/amd/display/modules/hdcp/hdcp_ddc.c. I also declared several of these arrays as having HDCP_MESSAGE_ID_MAX entries. This doesn't change the code, but it's just a belt and suspenders approach to try future proof the code.

Business impact

Successful exploitation of CVE-2021-47046, 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

• NVD
• Reference
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• Reference