CVE-2026-98453 smb: client: close handle after create-context parsing failure
A flaw in the Linux kernel SMB client fails to close handles on parsing errors, allowing remote attackers to exhaust server resources and cause denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98453?
CVE-2026-98453 is a denial of service vulnerability in Linux, published on 18 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
smb: client: close handle after create-context parsing failure
SMB2_open() accounts a successful CREATE response as a remote open before parsing its create contexts. If smb2_parse_contexts() rejects malformed context data, SMB2_open() returns without closing the handle, leaving the server-side handle open and num_remote_opens elevated.
Close the handle after a post-CREATE context parsing failure so the error path releases the remote resource and balances the open count.
Which versions are affected by CVE-2026-98453?
How do I fix CVE-2026-98453?
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-2026-98453 being exploited?
There is no known exploitation of CVE-2026-98453 in the wild and no public exploit code.
Sources
Also known as AZL-108876, BELL-CVE-2026-98453, DEBIAN-CVE-2026-98453, GHSA-8g43-4633-h8mf, UBUNTU-CVE-2026-98453.