Critical severity · published Aug 22, 2026
CVE-2026-74608
smb: client: Fix use-after-free in cifs_try_adding_channels()
9.8
CVSS
0.5%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix use-after-free in cifs_try_adding_channels() cifs_try_adding_channels() takes a temporary reference to an interface before dropping iface_lock. If cifs_ses_add_channel() fails, it drops that reference and then increments iface->weight_fulfilled. A concurrent interface list refresh can remove the list reference while channel creation is in progress. In that case, the failure-path kref_put() releases the last reference and frees iface. Updating weight_fulfilled afterward then accesses freed memory. Increment weight_fulfilled before dropping the temporary reference, keeping iface alive for the final access.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
cbc53148cc0946b72d62a3c53870cb22ce4ec284 before 64d7584e62ac8cdc750455c5fdc6008fc2de4f06; cff97d683a083b862a8bb24309e0f4d2d928128a before c292d4686f717c03e5022fc4ae7c782f39a94915; 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 before 47dfac48bce7198ad4f1a388fc8c9491f878ac3b; 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 before 1ffacbadc14530e55b8d86f7b917524f6a0fb891; 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 before 1305eadc6a7d78a8d0a52eee29ddd2d9e8a27805; 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 before 4986410316b1ae0e63c6ce418e4eb196723626e7; +5 more · source: vendor