CVE-2026-64123
In the Linux kernel, the following vulnerability has been resolved: net: hsr: defer node table free until after RCU readers HSR node-list and node-status generic-netlink operations run under rcu_read_lock().
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: net: hsr: defer node table free until after RCU readers HSR node-list and node-status generic-netlink operations run under rcu_read_lock(). They walk hsr->node_db through hsr_get_next_node() and hsr_get_node_data(), but RTM_DELLINK teardown removes the same node table with plain list_del() and frees each node immediately. That lets a generic-netlink reader hold a struct hsr_node pointer across hsr_dellink(). In a KASAN build, widening the reader window after hsr_get_next_node() obtains the node reproduces a slab-use-after-free when the reader copies node->macaddress_A; the freeing stack is hsr_del_nodes() from hsr_dellink(). Use list_del_rcu() and defer the free through the existing hsr_free_node_rcu() callback. This matches the lifetime rule used by the HSR prune paths, which already delete nodes with list_del_rcu() and call_rcu().
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0ea70fb46940620848c08d9d399455c9e82fecdbPatch
- https://git.kernel.org/stable/c/6324423a8e6591f41a16c09a8f9a84e554ac147cPatch
- https://git.kernel.org/stable/c/7713f4aafb577ff49fa67f0488d9c7dddc64d6cePatch
- https://git.kernel.org/stable/c/8be6685cdd1255bcc85f9b59e4bfc313aefc5c1bPatch
- https://git.kernel.org/stable/c/8c3af18bb0d7c921a5219194037509463eb2ffdePatch
- https://git.kernel.org/stable/c/aaec7096f9961eb223b5b149abe9495525c205d9Patch
- https://git.kernel.org/stable/c/c5580114e0492bcd2e0a37613ed4c311e3fa3d4dPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.