CVE-2019-3843 Privilege escalation in systemd

What is CVE-2019-3843?

CVE-2019-3843 is a medium-severity vulnerability in Canonical Ubuntu Linux, published on 26 Apr 2019. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

It was discovered that a systemd service that uses DynamicUser property can create a SUID/SGID binary that would be allowed to run as the transient service UID/GID even after the service is terminated. A local attacker may use this flaw to access resources that will be owned by a potentially different service in the future, when the UID/GID will be recycled.

Weakness: CWE-269, CWE-266

Which versions are affected by CVE-2019-3843?

It affects 7 products.

Products include Canonical Ubuntu Linux, Fedoraproject Fedora, Netapp Cn1610 Firmware, Netapp Hci Management Node, Netapp Snapprotect, Netapp Solidfire and 1 more.

How do I fix CVE-2019-3843?

Apply the vendor's patch.

Is CVE-2019-3843 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2019-3843 exists.

Public exploit code: 1 Exploit-DB entry.

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-2019-3843, GHSA-54p3-x8px-4jp3, UBUNTU-CVE-2019-3843.