CVE-2026-46243

What it is

In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.spnego descriptions cifs.spnego key descriptions contain authority-bearing fields such as pid, uid, creduid, and upcall_target that cifs.upcall treats as kernel-originating inputs. However, userspace can also create keys of this type through request_key(2) or add_key(2), allowing those fields to be supplied without CIFS origin. Only accept cifs.spnego descriptions while CIFS is using its private spnego_cred to request the key.

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-06-01 17:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-15 02:19 UTC Last updatedMost recent change to the record

Details

Published

2026-06-01 17:17 UTC

Last modified

2026-10-15 02:19 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-20 · Improper input validation

Record status

Modified

Affected

• Linux Kernel < 5.10.258
• Linux Kernel < 5.15.209
• Linux Kernel < 6.1.175
• Linux Kernel < 6.6.142
• Linux Kernel < 6.12.92
• Linux Kernel < 6.18.34
• Linux Kernel < 7.0.11
• Linux Kernel 2.6.24

Attack profile CVSS 3.1 · 7.1

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None