---
title: "CVE-2018-7750\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-2018-7750?format=md
keywords: index, follow
---

# CVE-2018-7750

Publication date 13 March 2018

Last updated 25 August 2025

---

Ubuntu priority

**High**

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

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2018-7750?format=md#impact-score)

Toggle side navigation

## Description

transport.py in the SSH server implementation of Paramiko before 1.17.6,
1.18.x before 1.18.5, 2.0.x before 2.0.8, 2.1.x before 2.1.5, 2.2.x before
2.2.3, 2.3.x before 2.3.2, and 2.4.x before 2.4.1 does not properly check
whether authentication is completed before processing other requests, as
demonstrated by channel-open. A customized SSH client can simply skip the
authentication step.

### From the Ubuntu Security Team

Matthijs Kooijman discovered that Paramiko's SSH server implementation
did not properly require authentication before processing requests. An
unauthenticated remote attacker could possibly use this to execute
arbitrary code.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| paramiko | 17.10 artful | Fixed 2.0.0-1ubuntu0.1 |
| 16.04 LTS xenial | Fixed 1.16.0-1ubuntu0.1 |
| 14.04 LTS trusty | Fixed 1.10.1-1git1ubuntu0.1 |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2018-7750?format=md#patch-details)

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| paramiko | * Upstream:   [fa29bd8](https://github.com/paramiko/paramiko/commit/fa29bd8446c8eab237f5187d28787727b4610516) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.8 · Critical

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.8 · Critical |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-7750)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-7750)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-7750)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2018-7750)

### Related Ubuntu Security Notices (USN)

+ [USN-3603-2](https://usn.ubuntu.com/USN-3603-2)
+ Paramiko vulnerability
+ 20 March 2018

+ [USN-3603-1](https://usn.ubuntu.com/USN-3603-1)
+ Paramiko vulnerability
+ 20 March 2018

### Other references

* <https://github.com/paramiko/paramiko/issues/1175>
* <https://github.com/paramiko/paramiko/blob/master/sites/www/changelog.rst>
* <https://www.cve.org/CVERecord?id=CVE-2018-7750>