---
title: "CVE-2018-6794\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2018-6794?format=md
keywords: index, follow
---

# CVE-2018-6794

Publication date 7 February 2018

Last updated 26 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**5.3 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2018-6794?format=md#impact-score)

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## Description

Suricata before 4.0.4 is prone to an HTTP detection bypass vulnerability in
detect.c and stream-tcp.c. If a malicious server breaks a normal TCP flow
and sends data before the 3-way handshake is complete, then the data sent
by the malicious server will be accepted by web clients such as a web
browser or Linux CLI utilities, but ignored by Suricata IDS signatures.
This mostly affects IDS signatures for the HTTP protocol and TCP stream
content; signatures for TCP packets will inspect such network traffic as
usual.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| suricata | 26.04 LTS resolute | Not affected |
| 25.10 questing | Not affected |
| 25.04 plucky | Not affected |
| 24.10 oracular | Not affected |
| 24.04 LTS noble | Not affected |
| 23.10 mantic | Not affected |
| 23.04 lunar | Not affected |
| 22.10 kinetic | Not affected |
| 22.04 LTS jammy | Not affected |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.10 groovy | Not in release |
| 20.04 LTS focal | Not in release |
| 19.10 eoan | Ignored end of life |
| 19.04 disco | Ignored end of life |
| 18.10 cosmic | Ignored end of life |
| 18.04 LTS bionic | Vulnerable |
| 17.10 artful | Ignored end of life |
| 16.04 LTS xenial | Vulnerable |
| 14.04 LTS trusty | Not in release |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.3 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | None |
  | Integrity impact | Low |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.3 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-6794)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-6794)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-6794)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2018-6794)

### Other references

* <https://redmine.openinfosecfoundation.org/issues/2427>
* <https://github.com/OISF/suricata/pull/3202/commits/e1ef57c848bbe4e567d5d4b66d346a742e3f77a1>
* <https://www.cve.org/CVERecord?id=CVE-2018-6794>