CVE-2021-47353: linux kernel vulnerability

What is known

In the Linux kernel, the following vulnerability has been resolved: udf: Fix NULL pointer dereference in udf_symlink function In function udf_symlink, epos.bh is assigned with the value returned by udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c and returns the value of sb_getblk function that could be NULL. Then, epos.bh is used without any check, causing a possible NULL pointer dereference when sb_getblk fails. This fix adds a check to validate the value of epos.bh.

Business impact

Successful exploitation of CVE-2021-47353, 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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