--- title: 'USN-4978-1: Firefox vulnerabilities | Ubuntu security notices' 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/notices/USN-4978-1 --- 1. [Ubuntu Security Notices](https://ubuntu.com/security/notices) 2. USN-4978-1 --- # USN-4978-1: Firefox vulnerabilities Publication date 2 June 2021 Overview Firefox could be made to crash or run programs as your login if it opened a malicious website. Releases [21.04](https://ubuntu.com/security/notices?release=hirsute) [20.10](https://ubuntu.com/security/notices?release=groovy) [20.04 LTS](https://ubuntu.com/security/notices?release=focal) [18.04 LTS](https://ubuntu.com/security/notices?release=bionic) --- Open side navigation ## Packages * [firefox](https://ubuntu.com/security/cves?package=firefox) - Mozilla Open Source web browser ## Details Multiple security issues were discovered in Firefox. If a user were tricked into opening a specially crafted website, an attacker could potentially exploit these to cause a denial of service, re-enable camera devices without an additional permission prompt, spoof the browser UI, or execute arbitrary code. ([CVE-2021-29959](https://ubuntu.com/security/CVE-2021-29959), [CVE-2021-29961](https://ubuntu.com/security/CVE-2021-29961), [CVE-2021-29966](https://ubuntu.com/security/CVE-2021-29966), [CVE-2021-29967](https://ubuntu.com/security/CVE-2021-29967)) It was discovered that filenames printed from private browsing mode were incorrectly retained in preferences. A local attacker could potentially exploit this to obtain sensitive information. ([CVE-2021-29960](https://ubuntu.com/security/CVE-2021-29960)) ## Update instructions After a standard system update you need to restart Firefox to make all the necessary changes. [Learn more about how to get the fixes.](https://ubuntu.com/security/cves/about#security) The problem can be corrected by updating your system to the following package versions: | Ubuntu Release | Package Version | | --- | --- | | 21.04 hirsute | [firefox](https://launchpad.net/ubuntu/+source/firefox) –  [89.0+build2-0ubuntu0.21.04.1](https://launchpad.net/ubuntu/+source/firefox/89.0+build2-0ubuntu0.21.04.1) | | | | 20.10 groovy | [firefox](https://launchpad.net/ubuntu/+source/firefox) –  [89.0+build2-0ubuntu0.20.10.1](https://launchpad.net/ubuntu/+source/firefox/89.0+build2-0ubuntu0.20.10.1) | | | | 20.04 LTS focal | [firefox](https://launchpad.net/ubuntu/+source/firefox) –  [89.0+build2-0ubuntu0.20.04.2](https://launchpad.net/ubuntu/+source/firefox/89.0+build2-0ubuntu0.20.04.2) | | | | 18.04 LTS bionic | [firefox](https://launchpad.net/ubuntu/+source/firefox) –  [89.0+build2-0ubuntu0.18.04.2](https://launchpad.net/ubuntu/+source/firefox/89.0+build2-0ubuntu0.18.04.2) | | | --- ### Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. [Get Ubuntu Pro](https://ubuntu.com/pro) ## References * [CVE-2021-29967](https://ubuntu.com/security/CVE-2021-29967) * [CVE-2021-29966](https://ubuntu.com/security/CVE-2021-29966) * [CVE-2021-29961](https://ubuntu.com/security/CVE-2021-29961) * [CVE-2021-29960](https://ubuntu.com/security/CVE-2021-29960) * [CVE-2021-29959](https://ubuntu.com/security/CVE-2021-29959) ## Related notices * [USN-4995-1](https://ubuntu.com/security/notices/USN-4995-1) * [USN-4995-2](https://ubuntu.com/security/notices/USN-4995-2)