CVE-2026-93210 smb: client: harden DFS cache against invalid target hints
A null pointer dereference in the Linux kernel SMB client DFS cache can cause a system crash, requiring a kernel patch.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-93210?
CVE-2026-93210 is a vulnerability in Linux, published on 24 Sep 2026. 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:
smb: client: harden DFS cache against invalid target hints
Currently, get_tgt_name() returns ERR_PTR(-ENOENT) when ce->tgthint is NULL, and dfs_cache_noreq_update_tgthint() assumes ce->tgthint is always valid.
In preparation for clearing ce->tgthint in free_tgts(), harden callers of get_tgt_name() against ERR_PTR results and harden dfs_cache_noreq_update_tgthint() against NULL pointer dereferences.
Which versions are affected by CVE-2026-93210?
How do I fix CVE-2026-93210?
Apply the vendor's patch.
Is CVE-2026-93210 being exploited?
There is no known exploitation of CVE-2026-93210 in the wild and no public exploit code.
Sources
Also known as AZL-103922, BELL-CVE-2026-93210, DEBIAN-CVE-2026-93210, GHSA-whr7-9fmh-x37r, UBUNTU-CVE-2026-93210.