CVE-2018-18956

The ProcessMimeEntity function in util-decode-mime.c in Suricata 4.x before 4.0.6 allows remote...

7.5 HighFix available

The ProcessMimeEntity function in util-decode-mime.c in Suricata 4.x before 4.0.6 allows remote attackers to cause a denial of service (segfault and daemon crash) via crafted input to the SMTP parser, as exploited in the wild in November 2018.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

2.82%Up 1.5 points since Apr 14, 2021

What each source reports

NVD Score used 7.5

Record: CVE-2018-18956
CVSS 3.0: 7.5 HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.0: 5.0 MediumAV:N/AC:L/Au:N/C:N/I:N/A:P
Weakness: CWE-119
Updated: 2026-11-02

CVE List No score

Record: CVE-2018-18956
Updated: 2026-11-02

EUVDEUVD-2018-10660 No score

Record: EUVD-2018-10660
Updated: 2026-11-03

GitHub AdvisoriesGHSA-mhv4-xgrg-gg58 7.5

The ProcessMimeEntity function in util-decode-mime.c in Suricata 4.x before 4.0.6 allows remote...

Record: GHSA-mhv4-xgrg-gg58
CVSS 3.0: 7.5 HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-119
Updated: 2026-11-02

OSV 7.5

Record: CVE-2018-18956
CVSS 3.0: 7.5 HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVDEBIAN-CVE-2018-18956 7.5

Record: DEBIAN-CVE-2018-18956
CVSS 3.0: 7.5 HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVUBUNTU-CVE-2018-18956 7.5

Record: UBUNTU-CVE-2018-18956
CVSS 3.0: 7.5 HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

Affected products

suricata-ids suricata

Affected packages

Affected packages
Package	Affected	Fixed
`suricata` Debian:13	before 1:4.0.6-1	1:4.0.6-1
`suricata` Debian:14	before 1:4.0.6-1	1:4.0.6-1
`suricata` Ubuntu:16.04:LTS	All versions, plus listed versions 2.0.8-1build12.0.9-12.0.10-12.0.10-22.0.11-13.0-1	None known
`suricata` Ubuntu:18.04:LTS	All versions, plus listed versions 3.2-2ubuntu3	None known

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2018-18956 is a high vulnerability (CVSS 7.5) in Suricata-ids Suricata, published November 5, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.82%, the 86th percentile. Fixed in suricata 1:4.0.6-1.