CVE-2025-38678 netfilter: nf_tables: reject duplicate device on updates
A local attacker can trigger a kernel warning and potential instability by submitting duplicate devices in netfilter updates, requiring a kernel patch.
- 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-2025-38678?
CVE-2025-38678 is a high-severity denial of service vulnerability in Linux kernel, published on 3 Sep 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:
netfilter: nf_tables: reject duplicate device on updates
A chain/flowtable update with duplicated devices in the same batch is possible. Unfortunately, netdev event path only removes the first device that is found, leaving unregistered the hook of the duplicated device.
Check if a duplicated device exists in the transaction batch, bail out with EEXIST in such case.
WARNING is hit when unregistering the hook:
[49042.221275] WARNING: CPU: 4 PID: 8425 at net/netfilter/core.c:340 nf_hook_entry_head+0xaa/0x150 [49042.221375] CPU: 4 UID: 0 PID: 8425 Comm: nft Tainted: G S 6.16.0+ #170 PREEMPT(full) [...] [49042.221382] RIP: 0010:nf_hook_entry_head+0xaa/0x150
Which versions are affected by CVE-2025-38678?
It affects 1 product.
Linux distribution packages (5)
kernel-livepatch-SLE15-SP4_Update_44 SUSE:Linux Enterprise Live Patching 15 SP4 | All versions | 2-150400.2.1 |
kernel-livepatch-SLE15-SP5_Update_30 SUSE:Linux Enterprise Live Patching 15 SP5 | All versions | 2-150500.2.1 |
kernel-livepatch-SLE15-SP6_Update_15 SUSE:Linux Enterprise Live Patching 15 SP6 | All versions | 2-150600.2.1 |
kernel-livepatch-SLE15-SP7-RT_Update_4 SUSE:Linux Enterprise Live Patching 15 SP7 | All versions | 2-150700.2.1 |
kernel-livepatch-SLE15-SP7_Update_4 SUSE:Linux Enterprise Live Patching 15 SP7 | All versions | 2-150700.2.1 |
Products include Linux kernel.
How do I fix CVE-2025-38678?
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-2025-38678 being exploited?
There is no known exploitation of CVE-2025-38678 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-66773, AZL-70774, BELL-CVE-2025-38678, DEBIAN-CVE-2025-38678, GHSA-g7rm-8pw5-wvg2, ROOT-OS-DEBIAN-11-CVE-2025-38678 and 8 more.