USN-3944-1: wpa_supplicant and hostapd vulnerabilities

10 April 2019

wpa vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 18.10
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS


Several security issues were fixed in wpa_supplicant and hostapd.

Software Description

  • wpa - client support for WPA and WPA2


It was discovered that wpa_supplicant and hostapd were vulnerable to a side channel attack against EAP-pwd. A remote attacker could possibly use this issue to recover certain passwords. (CVE-2019-9495)

Mathy Vanhoef discovered that wpa_supplicant and hostapd incorrectly validated received scalar and element values in EAP-pwd-Commit messages. A remote attacker could possibly use this issue to perform a reflection attack and authenticate without the appropriate password. (CVE-2019-9497, CVE-2019-9498, CVE-2019-9499)

It was discovered that hostapd incorrectly handled obtaining random numbers. In rare cases where the urandom device isn’t available, it would fall back to using a low-quality PRNG. This issue only affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-10743)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.10
hostapd - 2:2.6-18ubuntu1.1
wpasupplicant - 2:2.6-18ubuntu1.1
Ubuntu 18.04 LTS
hostapd - 2:2.6-15ubuntu2.2
wpasupplicant - 2:2.6-15ubuntu2.2
Ubuntu 16.04 LTS
hostapd - 2.4-0ubuntu6.4
wpasupplicant - 2.4-0ubuntu6.4
Ubuntu 14.04 LTS
hostapd - 2.1-0ubuntu1.7
wpasupplicant - 2.1-0ubuntu1.7

To update your system, please follow these instructions:

After a standard system update you need to reboot your computer to make all the necessary changes.