CVE-2026-43112

In the Linux kernel, the following vulnerability has been resolved: fs/smb/client: fix out-of-bounds read in cifs_sanitize_prepath When cifs_sanitize_prepath is called with an empty string or a string containing only delimiters (e.g., "/"), the current logic attempts to check *(cursor2 - 1) before cursor2 has advanced. This results in an out-of-bounds read. This patch adds an early exit check after stripping prepended delimiters. If no path content remains, the function returns NULL. The bug was identified via manual audit and verified using a standalone test case compiled with AddressSanitizer, which triggered a SEGV on affected inputs.

What this means for your business

It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 28% of all known flaws.

What to do

1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

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Scoring

CVSS: 8.8 (v3.1)
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-125
Assigned by: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Dates

Published: 2026-05-06
Last modified: 2026-09-18
Sources: NVD

Affected products

Linux Linux Kernel5.16.1 - 6.6.136, 6.7 - 6.12.83, 6.13 - 6.18.24, 6.19 - 6.19.14, 5.16, 7.0

As listed in the NVD configuration data. Not a statement about your estate.