CVE-2026-23001: macvlan: fix possible UAF in macvlan_forward_source()
In the Linux kernel, the following vulnerability has been resolved:
macvlan: fix possible UAF in macvlanforwardsource()
Add RCU protection on (struct macvlansourceentry)->vlan.
Whenever macvlanhashdelsource() is called, we must clear entry->vlan pointer before RCU grace period starts.
This allows macvlanforwardsource() to skip over entries queued for freeing.
Note that macvlandev are already RCU protected, as they are embedded in a standard netdev (netdevpriv(ndev)).
https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u
Other sources
In the Linux kernel, the following vulnerability has been resolved:
macvlan: fix possible UAF in macvlanforwardsource()
Add RCU protection on (struct macvlansourceentry)->vlan.
Whenever macvlanhashdelsource() is called, we must clear entry->vlan pointer before RCU grace period starts.
This allows macvlanforwardsource() to skip over entries queued for freeing.
Note that macvlandev are already RCU protected, as they are embedded in a standard netdev (netdevpriv(ndev)).
https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE/T/#u
— Red Hat
In the Linux kernel, the following vulnerability has been resolved:
macvlan: fix possible UAF in macvlanforwardsource()
Add RCU protection on (struct macvlansourceentry)-vlan.
Whenever macvlanhashdelsource() is called, we must clear entry-vlan pointer before RCU grace period starts.
This allows macvlanforwardsource() to skip over entries queued for freeing.
Note that macvlandev are already RCU protected, as they are embedded in a standard netdev (netdevpriv(ndev)).
https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u
— IBM
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-23001?
CVE-2026-23001 has been classified as a high-severity vulnerability due to the potential use-after-free condition that can lead to security issues.
How do I fix CVE-2026-23001?
To address CVE-2026-23001, you should update your Linux kernel to the latest patched version provided by your distribution.
What systems are affected by CVE-2026-23001?
CVE-2026-23001 affects the macvlan implementation in the Linux kernel.
What is the impact of CVE-2026-23001?
The impact of CVE-2026-23001 may include system crashes or exploitation leading to arbitrary code execution.
When was CVE-2026-23001 published?
CVE-2026-23001 was published as a vulnerability in 2026.