CVE-2026-43406: linux kernel vulnerability

CVE-2026-43406: critical vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-43406CVSS 9.1Linux

CVE-2026-43406: linux kernel vulnerability

CVE-2026-43406: critical vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
9.1 CRITICAL
EPSS
40.04%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: libceph: prevent potential out-of-bounds reads in process_message_header() If the message frame is (maliciously) corrupted in a way that the length of the control segment ends up being less than the size of the message header or a different frame is made to look like a message frame, out-of-bounds reads may ensue in process_message_header(). Perform an explicit bounds check before decoding the message header.

Business impact

Successful exploitation of CVE-2026-43406, a critical vulnerability (CVSS 9.1) 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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