CVE-2026-90175 smb: server: fix leak of ksmbd_ipc_login_request_ext() returned buffer
A memory leak in the Linux kernel's ksmbd SMB server allows local attackers to exhaust kernel memory, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90175?
CVE-2026-90175 is a memory corruption vulnerability in Linux, published on 17 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: server: fix leak of ksmbd_ipc_login_request_ext() returned buffer
Free it unconditionally after ksmbd_alloc_user() calls.
kmemleak splat: unreferenced object 0xffff888103b83540 (size 192): comm "pool-0", pid 16970, jiffies 4377290937 hex dump (first 32 bytes): 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 408ccc66): __kvmalloc_node_noprof+0x730/0x920 handle_generic_event+0xec/0x1a0 [ksmbd] genl_family_rcv_msg_doit+0xe0/0x130 genl_rcv_msg+0x181/0x290 netlink_rcv_skb+0x4f/0x100 genl_rcv+0x28/0x40 netlink_unicast+0x1e6/0x2c0 netlink_sendmsg+0x20a/0x450 ____sys_sendmsg+0x2e8/0x310 ___sys_sendmsg+0x78/0xc0 __sys_sendmsg+0x63/0xc0 do_syscall_64+0xa1/0x670 entry_SYSCALL_64_after_hwframe+0x76/0x7e
Which versions are affected by CVE-2026-90175?
How do I fix CVE-2026-90175?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-90175 being exploited?
There is no known exploitation of CVE-2026-90175 in the wild and no public exploit code.
Sources
Also known as AZL-102453, BELL-CVE-2026-90175, DEBIAN-CVE-2026-90175, GHSA-jxh3-3qm5-qh2j, UBUNTU-CVE-2026-90175.