CVE-2026-64598 smb/client: Fix error code in smb2_aead_req_alloc()
An integer overflow in the Linux kernel SMB client causes a crash when dereferencing an invalid error pointer, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-64598?
CVE-2026-64598 is a high-severity vulnerability in Linux, published on 6 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
In the Linux kernel, the following vulnerability has been resolved:
smb/client: Fix error code in smb2_aead_req_alloc()
The "*num_sgs" variable is a u32 so "ERR_PTR(*num_sgs)" doesn't work. We would have to do something similar to the previous line where it's cast to int and then long. However, it's simpler to store the return in an int ret variable.
This bug would eventually result in a crash when dereference the invalid error pointer.
Weakness: CWE-190
Which versions are affected by CVE-2026-64598?
How do I fix CVE-2026-64598?
Apply the vendor's patch.
Is CVE-2026-64598 being exploited?
There is no known exploitation of CVE-2026-64598 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-64598, DEBIAN-CVE-2026-64598, GHSA-3qwv-9mh7-f8fm, UBUNTU-CVE-2026-64598.