What’s Vulnerable › Vulnerabilities

CVE-2018-1139

• Severity: high (CVSS 8.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-08-22 · updated 2026-06-17
• Weakness: CWE-20

Description

A flaw was found in the way samba before 4.7.9 and 4.8.4 allowed the use of weak NTLMv1 authentication even when NTLMv1 was explicitly disabled. A man-in-the-middle attacker could use this flaw to read the credential and other details passed between the samba server and client.

Affected products

• Canonical Ubuntu Linux: 14.04, 16.04, 18.04
• RedHat Enterprise Linux Desktop: 7.0
• RedHat Enterprise Linux Server: 7.0
• RedHat Enterprise Linux Workstation: 7.0
• Samba: from 4.7.0 before 4.7.9; from 4.8.0 before 4.8.4 — fixed in 4.7.9, 4.8.4

How to fix

Upgrade to a fixed version: Samba 4.7.9, 4.8.4. Check the vendor advisory for mitigations.

References

• http://www.securityfocus.com/bid/105084
• https://access.redhat.com/errata/RHSA-2018:2612
• https://access.redhat.com/errata/RHSA-2018:2613
• https://access.redhat.com/errata/RHSA-2018:3056
• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-1139
• https://security.gentoo.org/glsa/202003-52
• https://security.netapp.com/advisory/ntap-20180814-0001/
• https://usn.ubuntu.com/3738-1/
• https://www.samba.org/samba/security/CVE-2018-1139.html
• http://www.securityfocus.com/bid/105084
• https://access.redhat.com/errata/RHSA-2018:2612
• https://access.redhat.com/errata/RHSA-2018:2613

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