Public exploit available
Public proof-of-concept or exploit code exists (ExploitDB / Metasploit / Nuclei).

CVE-2018-18397Incorrect Authorization in Kernel

Severity
5.5MEDIUMNVD
EPSS
0.1%
top 79.21%
CISA KEV
Not in KEV
Exploit
PoC available
Public exploit / PoC exists
Timeline
PublishedDec 12
Latest updateMay 13

Description

The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs file (if the user has read-only access to that file, and that file contains holes), related to fs/userfaultfd.c and mm/userfaultfd.c.

CVSS vector

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NExploitability: 1.8 | Impact: 3.6

Affected Packages7 packages

Also affects: Ubuntu Linux 14.04, 16.04, 18.04, 18.10, Enterprise Linux 7.4, 7.6, 7.5, Openshift Container Platform 3.11

Patches

🔴Vulnerability Details

6
GHSA
GHSA-7cx6-7887-9rwv: The userfaultfd implementation in the Linux kernel before 42022-05-13
OSV
linux-hwe, linux-azure vulnerabilities2019-03-06
OSV
linux-hwe, linux-aws-hwe, linux-azure, linux-gcp, linux-oracle vulnerabilities2019-03-05
OSV
linux, linux-aws, linux-gcp, linux-kvm, linux-oem, linux-oracle, linux-raspi2 vulnerabilities2019-03-05
OSV
CVE-2018-18397: The userfaultfd implementation in the Linux kernel before 42018-12-12

📋Vendor Advisories

6
Ubuntu
Linux kernel (HWE) vulnerabilities2019-03-06
Ubuntu
Linux kernel vulnerabilities2019-03-06
Ubuntu
Linux kernel vulnerabilities2019-03-05
Ubuntu
Linux kernel (HWE) vulnerabilities2019-03-05
Red Hat
kernel: userfaultfd bypasses tmpfs file permissions2018-11-26

💬Community

2
Bugzilla
CVE-2018-18397 kernel: userfaultfd bypasses tmpfs file permissions [fedora-all]2018-12-12
Bugzilla
CVE-2018-18397 kernel: userfaultfd bypasses tmpfs file permissions2018-10-22
CVE-2018-18397 — Incorrect Authorization in Kernel | cvebase