Use After Free Affecting linux-qemu-melange package, versions <6.18.49-r2


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.13% (3rd percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LINUXQEMUMELANGE-19656023
  • published10 Sept 2026
  • disclosed19 Jul 2026

Introduced: 19 Jul 2026

CVE-2026-64123  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Chainguard linux-qemu-melange to version 6.18.49-r2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream linux-qemu-melange package and not the linux-qemu-melange package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

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 Base Scores

version 3.1