CVE-2018-13405

What it is

The inode_init_owner function in fs/inode.c in the Linux kernel through 3.16 allows local users to create files with an unintended group ownership, in a scenario where a directory is SGID to a certain group and is writable by a user who is not a member of that group. Here, the non-member can trigger creation of a plain file whose group ownership is that group. The intended behavior was that the non-member can trigger creation of a directory (but not a plain file) whose group ownership is that group. The non-member can escalate privileges by making the plain file executable and SGID.

At a glance

Exploitability

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

Exploit odds

1.0% chance of exploitation in the next 30 days (EPSS).

Fix

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

Timeline

1. 2018-07-06 14:29 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 01:39 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 1.0% in the next 30 days (EPSS).
• Severity: 7.8 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2018-07-06 14:29 UTC

Last modified

2026-06-17 01:39 UTC

Exploit probability

1.0% · EPSS, next 30 days

Weakness

CWE-269 · Improper privilege management

Record status

Modified

Affected

• Linux Kernel ≤ 3.16
• Debian Linux 8.0
• Debian Linux 9.0
• Canonical Ubuntu Linux 14.04
• Canonical Ubuntu Linux 16.04
• Canonical Ubuntu Linux 18.04
• Fedoraproject Fedora 34
• Fedoraproject Fedora 35

Attack profile CVSS 3.1 · 7.8

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2018-13405.md and follow it. Check whether this project is affected by CVE-2018-13405. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge