CVE-2026-89634 Linux Kernel smb client - Out of Bounds Read & Denial of Service

Linux kernel contains a buffer overflow caused by an ALIGN() overflow in smb client symlink_data() error context loop, letting attackers cause out-of-bounds read or infinite loop, exploit requires crafted SMB response.

CVSS base score 9.1 /10
Critical
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.69% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Out of Bounds Read
Impact
Denial Of Service, Information Disclosure
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Published
11 September 2026
Updated
15 October 2026

Vendor fix

Update to the latest Linux kernel version containing the fix.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

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