CVE-2018-18397 Missing authorization in n/a

What is CVE-2018-18397?

CVE-2018-18397 is a medium-severity missing authorization vulnerability in Canonical Ubuntu Linux, published on 12 Dec 2018. It can only be exploited from the same machine or local network, with no action from the victim.

Official 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.

Weakness: CWE-863

Which versions are affected by CVE-2018-18397?

It affects 10 products.

Products include Canonical Ubuntu Linux, Linux kernel, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus and 4 more.

How do I fix CVE-2018-18397?

Apply the vendor's patch.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2018-18397 being exploited?

There is no known exploitation of CVE-2018-18397 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2018-18397, GHSA-7cx6-7887-9rwv, RHSA-2019:0202, RHSA-2019:0324, UBUNTU-CVE-2018-18397.