---
title: "CVE-2017-18264\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-2017-18264?format=md
keywords: index, follow
---

# CVE-2017-18264

Publication date 1 May 2018

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2017-18264?format=md#impact-score)

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## Description

An issue was discovered in libraries/common.inc.php in phpMyAdmin 4.0
before 4.0.10.20, 4.4.x, 4.6.x, and 4.7.0 prereleases. The restrictions
caused by $cfg['Servers'][$i]['AllowNoPassword'] = false are bypassed under
certain PHP versions (e.g., version 5). This can allow the login of users
who have no password set even if the administrator has set
$cfg['Servers'][$i]['AllowNoPassword'] to false (which is also the
default). This occurs because some implementations of the PHP substr
function return false when given '' as the first argument.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| phpmyadmin | 22.04 LTS jammy | Not affected |
| 21.10 impish | Not affected |
| 21.04 hirsute | Not affected |
| 20.10 groovy | Not affected |
| 20.04 LTS focal | Not affected |
| 19.10 eoan | Not in release |
| 19.04 disco | Not affected |
| 18.10 cosmic | Not affected |
| 18.04 LTS bionic | Not affected |
| 17.10 artful | Not affected |
| 16.04 LTS xenial | Fixed 4:4.5.4.1-2ubuntu2.1+esm3  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 4:4.0.10-1ubuntu0.1+esm4  Ubuntu Pro |

---

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

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## 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:3.0/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-2017-18264)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2017-18264)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2017-18264)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2017-18264)

### Related Ubuntu Security Notices (USN)

+ [USN-4843-1](https://usn.ubuntu.com/USN-4843-1)
+ phpMyAdmin vulnerabilities
+ 16 March 2021

### Other references

* <https://www.phpmyadmin.net/security/PMASA-2017-8/>
* <https://github.com/phpmyadmin/phpmyadmin/commit/7232271a379396ca1d4b083af051262057003c41 (4.7-branch)>
* <https://github.com/phpmyadmin/phpmyadmin/commit/b6ca92cc75c8a16001425be7881e73430bcc35b8 (4.0-branch)>
* <https://www.cve.org/CVERecord?id=CVE-2017-18264>