CVE-2024-49936: net/xen-netback: prevent UAF in xenvif_flush_hash()

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-10-21 · updated 2026-08-04
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: net/xen-netback: prevent UAF in xenvif_flush_hash() During the list_for_each_entry_rcu iteration call of xenvif_flush_hash, kfree_rcu does not exist inside the rcu read critical section, so if kfree_rcu is called when the rcu grace period ends during the iteration, UAF occurs when accessing head->next after the entry becomes free. Therefore, to solve this, you need to change it to list_for_each_entry_safe.

Affected products

Linux kernel: before 5.10.227; from 5.11 before 5.15.168; from 5.16 before 6.1.113; from 6.2 before 6.6.55; from 6.7 before 6.10.14; from 6.11 before 6.11.3 — fixed in 5.10.227, 5.15.168, 6.1.113, 6.10.14, 6.11.3, 6.6.55

How to fix

Upgrade to a fixed version: Linux kernel 5.10.227, 5.15.168, 6.1.113, 6.10.14. Check the vendor advisory for mitigations.

References

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