CVE-2026-89680 nfsd: fix nfsd_file leak on inter-server COPY setup failure
A resource leak in the Linux kernel NFS server allows attackers to exhaust memory via failed inter-server COPY operations, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89680?
CVE-2026-89680 is a high-severity denial of service vulnerability in Linux, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix nfsd_file leak on inter-server COPY setup failure
When nfsd4_setup_inter_ssc() fails, nfsd4_copy() returns nfserr_offload_denied directly, bypassing the out: label where release_copy_files() would drop the nf_dst reference taken by nfs4_preprocess_stateid_op(). Each failed inter-server COPY leaks one nfsd_file, pinning file/inode/dentry/vfsmount.
Fix by setting status and jumping to out: instead of returning directly.
Which versions are affected by CVE-2026-89680?
How do I fix CVE-2026-89680?
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-2026-89680 being exploited?
There is no known exploitation of CVE-2026-89680 in the wild and no public exploit code.
Sources
Also known as AZL-100395, BELL-CVE-2026-89680, DEBIAN-CVE-2026-89680, GHSA-x88v-7xqf-ff34, UBUNTU-CVE-2026-89680.