CVE-2020-14303

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-07-06 · updated 2026-06-17
Weakness: CWE-834

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.

Affected products

Canonical Ubuntu Linux: 12.04, 14.04, 16.04, 18.04, 20.04
Debian Linux: 9.0
Fedoraproject Fedora: 31
openSUSE Leap: 15.1, 15.2
Samba: from 4.10.0 before 4.10.17; from 4.11.0 before 4.11.11; from 4.12.0 before 4.12.4 — fixed in 4.10.17, 4.11.11, 4.12.4

How to fix

Upgrade to a fixed version: Samba 4.10.17, 4.11.11, 4.12.4. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00030.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00054.html
http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00002.html
https://bugzilla.redhat.com/show_bug.cgi?id=1851298%3B
https://lists.debian.org/debian-lts-announce/2020/11/msg00041.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6YLNQ5GRXUKYRUAOFZ4DUBVN4SMTL6Q2/
https://security.gentoo.org/glsa/202007-15
https://security.netapp.com/advisory/ntap-20200709-0003/
https://usn.ubuntu.com/4454-1/
https://usn.ubuntu.com/4454-2/
https://www.samba.org/samba/security/CVE-2020-14303.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00030.html

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