CVE-2020-14303 Denial of service in Samba

What is CVE-2020-14303?

CVE-2020-14303 is a high-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 6 Jul 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A flaw was found in the AD DC NBT server in all Samba versions before 4.10.17, before 4.11.11 and before 4.12.4. A samba user could send an empty UDP packet to cause the samba server to crash.

Weakness: CWE-834

Which versions are affected by CVE-2020-14303?

It affects 5 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Samba Samba.

How do I fix CVE-2020-14303?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2020-14303 being exploited?

There is no known exploitation of CVE-2020-14303 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 ALPINE-CVE-2020-14303, DEBIAN-CVE-2020-14303, ECHO-e844-254c-98eb, GHSA-gm89-9qf3-7p24, UBUNTU-CVE-2020-14303, USN-4454-1 and 1 more.