CVE-2019-18198 Use after free in n/a

What is CVE-2019-18198?

CVE-2019-18198 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 18 Oct 2019. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel before 5.3.4, a reference count usage error in the fib6_rule_suppress() function in the fib6 suppression feature of net/ipv6/fib6_rules.c, when handling the FIB_LOOKUP_NOREF flag, can be exploited by a local attacker to corrupt memory, aka CID-ca7a03c41753.

Weakness: CWE-772

Which versions are affected by CVE-2019-18198?

It affects 2 products.

Products include Canonical Ubuntu Linux, Linux kernel.

How do I fix CVE-2019-18198?

No fix has been published for CVE-2019-18198 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2019-18198 being exploited?

There is no known exploitation of CVE-2019-18198 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 CVE-2021-3892, GHSA-3wc6-3hc2-3wc8, UBUNTU-CVE-2019-18198.