CVE-2026-97922

/// Technical description

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

tracing: Free histogram var refs regardless of how often they are referenced

Using the same variable three or more times in one hist trigger leaks the

variable reference and its strings when the trigger is removed.

commit 656fe2ba85e8 ("tracing: Use hist trigger's var_ref array to destroy

var_refs") made a trigger's var_refs[] array the only owner of a var ref:

destroy_hist_field() returns early for HIST_FIELD_FL_VAR_REF, so the field

expressions never destroy one. One entry, freed once, no count needed.

commit 8bcebc77e85f ("tracing: Fix histogram code when expression has same

var as value") then made repeated references share one object and added a

count of them. Only the increment side exists, since those expressions

still return early and never drop a reference, so __destroy_hist_field()

sees how many references were created rather than how many are left. It

frees when the decremented count is 0 or 1, so two re

/// 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