CVE-2026-64123

net: hsr: defer node table free until after RCU readers

HIGH
7.8
CVSS Score
Published: July 19, 2026 at 03:40 PM UTC
Updated: October 19, 2026 at 09:17 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.1%
SSVC
No known 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().

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.11 ≤ v < 5.15.2105.16 ≤ v < 6.1.1765.2.12 ≤ v < 5.10.2596.13 ≤ v < 7.0.116.2 ≤ v < 6.6.1436.7 ≤ v < 6.12.935.2.127.17.1 rc17.1 rc27.1 rc37.1 rc48523d5a2f4a9e4202e0d282c164d453cabe2d2b9a1e627405d68d475a3c1f35e685ccfb5bbe668
Vendor states this is fixed in 0ea70fb46940620848c08d9d399455c9e82fecdb (fixed)
Vendor states this is fixed in 6324423a8e6591f41a16c09a8f9a84e554ac147c (fixed)
Vendor states this is fixed in 7713f4aafb577ff49fa67f0488d9c7dddc64d6ce (fixed)
Vendor states this is fixed in 8be6685cdd1255bcc85f9b59e4bfc313aefc5c1b (fixed)
Vendor states this is fixed in 8c3af18bb0d7c921a5219194037509463eb2ffde (fixed)
Vendor states this is fixed in aaec7096f9961eb223b5b149abe9495525c205d9 (fixed)
Vendor states this is fixed in c5580114e0492bcd2e0a37613ed4c311e3fa3d4d (fixed)
Vendor states this is fixed in 5.10.259 (unaffected)
Vendor states this is fixed in 5.15.210 (unaffected)
Vendor states this is fixed in 5.3 (unaffected)
Vendor states this is fixed in 6.1.176 (unaffected)
Vendor states this is fixed in 6.12.93 (unaffected)
Vendor states this is fixed in 6.18.57 (unaffected)
Vendor states this is fixed in 6.6.143 (unaffected)
Vendor states this is fixed in 7.0.11 (unaffected)
Vendor states this is fixed in 7.1 (unaffected)

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-416

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