USN-3918-1: Firefox vulnerabilities

Published Mar 21, 2019
·
Updated

Multiple security issues were discovered in Firefox. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit these to cause a denial of service via application crash, denial of service via successive FTP authorization prompts or modal alerts, trick the user with confusing permission request prompts, obtain sensitive information, conduct social engineering attacks, or execute arbitrary code. (CVE-2019-9788, CVE-2019-9789, CVE-2019-9790, CVE-2019-9791, CVE-2019-9792, CVE-2019-9795, CVE-2019-9796, CVE-2019-9797, CVE-2019-9799, CVE-2019-9802, CVE-2019-9805, CVE-2019-9806, CVE-2019-9807, CVE-2019-9808, CVE-2019-9809) A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. If a user were tricked in to opening a specially crafted website with Spectre mitigations disabled, an attacker could potentially exploit this to cause a denial of service, or execute arbitrary code. (CVE-2019-9793) It was discovered that Upgrade-Insecure-Requests was incorrectly enforced for same-origin navigation. An attacker could potentially exploit this to conduct machine-in-the-middle (MITM) attacks. (CVE-2019-9803)

Affected Software

6 affected componentsFixes available
All of the following
ubuntu/firefox<66.0+build3-0ubuntu0.18.10.1
66.0+build3-0ubuntu0.18.10.1
Ubuntu Ubuntu=18.10
All of the following
ubuntu/firefox<66.0+build3-0ubuntu0.18.04.1
66.0+build3-0ubuntu0.18.04.1
Ubuntu Ubuntu=18.04
All of the following
ubuntu/firefox<66.0+build3-0ubuntu0.16.04.2
66.0+build3-0ubuntu0.16.04.2
Ubuntu Ubuntu=16.04

Event History

Mar 21, 2019
Advisory Published
via Ubuntu·12:00 AM

Frequently Asked Questions

1

What are the vulnerabilities addressed by USN-3918-1?

Multiple security issues were discovered in Firefox.

2

What is the severity of USN-3918-1?

The severity of USN-3918-1 is not specified.

3

How can these vulnerabilities be exploited?

These vulnerabilities can be exploited by tricking a user into opening a specially crafted website.

4

How can an attacker exploit the vulnerabilities in USN-3918-1?

An attacker can exploit the vulnerabilities to cause a denial of service via application crash, denial of service via successive FTP authorization prompts or modal alerts, or trick the user into executing arbitrary code.

5

How can I fix the vulnerabilities in USN-3918-1?

To fix the vulnerabilities, update Firefox to version 66.0+build3-0ubuntu0.18.10.1 if you are using Ubuntu 18.10, version 66.0+build3-0ubuntu0.18.04.1 if you are using Ubuntu 18.04, or version 66.0+build3-0ubuntu0.16.04.2 if you are using Ubuntu 16.04.

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