CVE Catalog

CVE-2026-98235

Low risk· EPSS 7%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.18%

7th percentile - higher than 7% of all known CVEs

Summary

In the Linux kernel net/sched subsystem, tcf_action_put_many() uses the tcf_act_for_each_action() iterator, which stops at the first NULL slot. When a batched RTM_DELACTION request stops at an action bound to a filter, references on subsequent actions are not released, leaking a reference and allowing a later delete of an unbound action to return success without removing it from the IDR.

Risk Assessment

The reference leak can prevent actions from being deleted, leave the qdisc subsystem in an inconsistent state, and potentially be exploited for further attacks or network stack destabilization.

Recommendation

Update the Linux kernel to a version containing the fix that walks the full array in tcf_action_put_many() and skips NULL slots.

Related vulnerabilities

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_api: release tail references on DELACTION failure A batched RTM_DELACTION request takes a temporary reference on each action before attempting any deletion. tcf_action_delete() clears each processed slot and drops its temporary reference before attempting the deletion. If deletion fails, tca_action_gd() calls tcf_action_put_many() to release the remaining references, but its tcf_act_for_each_action() iterator stops at the first NULL slot. When a batch stops at an action bound to a filter, this leaks a reference on each subsequent action. A later delete of an unbound action can then return success without removing it from the IDR. Walk the full array in tcf_action_put_many() and skip NULL slots to release the references held on the unprocessed actions.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS