CVE-2026-98552

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

perf/core: Fix a refcount leak in attach_perf_ctx_data()

The attach_perf_ctx_data() can race on global and !global cases. The

global case is protected by global_ctx_data_rwsem and shares a single

reference count using perf_ctx_data.global field.

But when it races with !global case, it may miss to set the global field

and result in a reference count leak.

CPU1 CPU2

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attach_task_ctx_data(.global=1) attach_task_ctx_data(.global=0)

cd1 = alloc_perf_ctx_data(); cd2 = alloc_perf_ctx_data();

// { .global = 0, .refcount = 1 };

try_cmpxchg(); // success,

// task->perf_ctx_data = cd2

try_cmpxhg(); // fail; old = cd2

refcount_inc_not_zero(&old->refcount); // success

// old.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References