A critical out-of-bounds heap read vulnerability in the Linux kernel allows unauthenticated attackers to potentially access sensitive memory or cause system instability.

The machine_resolve function fails to validate CPU indices against the available CPU count when processing perf.data samples. Because this data is untrusted, an attacker can supply a crafted file to trigger an out-of-bounds heap read, which may lead to information disclosure or denial of service.

The vulnerability carries a CVSS score of 9.1, reflecting its potential for remote exploitation by unauthenticated actors. Successful exploitation could lead to the exposure of sensitive kernel memory, which might include cryptographic keys or authentication tokens, or result in a system crash that disrupts critical business operations.

Immediate Action: Update the Linux kernel to version 6.18.40, 7.1.5, or later, as these versions contain the necessary bounds-checking logic.

Proactive Monitoring: Monitor system logs for unexpected perf tool crashes or segmentation faults that may indicate an attempt to process malicious perf.data files.

Compensating Controls: Restrict access to the perf tool and limit the ability of untrusted users to generate or import perf.data files on production systems.

Public Exploit Available: No

The severity of this vulnerability necessitates immediate attention, particularly in environments where users may provide external or untrusted perf.data files for analysis. Organizations should prioritize updating their Linux kernels to the specified fixed releases to eliminate the risk of out-of-bounds memory access. Failure to patch leaves the kernel exposed to potential memory corruption and unauthorized data exposure.