CVE-2022-49903 ipv6: fix WARNING in ip6_route_net_exit_late()
A flaw in the Linux kernel IPv6 routing initialization can trigger a kernel warning and potential crash during network namespace cleanup, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-49903?
CVE-2022-49903 is a medium-severity denial of service vulnerability in Linux kernel, published on 1 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix WARNING in ip6_route_net_exit_late()
During the initialization of ip6_route_net_init_late(), if file ipv6_route or rt6_stats fails to be created, the initialization is successful by default. Therefore, the ipv6_route or rt6_stats file doesn't be found during the remove in ip6_route_net_exit_late(). It will cause WRNING.
The following is the stack information: name 'rt6_stats' WARNING: CPU: 0 PID: 9 at fs/proc/generic.c:712 remove_proc_entry+0x389/0x460 Modules linked in: Workqueue: netns cleanup_net RIP: 0010:remove_proc_entry+0x389/0x460 PKRU: 55555554 Call Trace: <TASK> ops_exit_list+0xb0/0x170 cleanup_net+0x4ea/0xb00 process_one_work+0x9bf/0x1710 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 </TASK>
Which versions are affected by CVE-2022-49903?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49903?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2022-49903 being exploited?
There is no known exploitation of CVE-2022-49903 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49903, GHSA-7m6j-5mcx-6jmq, UBUNTU-CVE-2022-49903.