USN-3477-2: Firefox regression

Ubuntu Security Notice USN-3477-2

27th November, 2017

firefox regression

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

  • Ubuntu 17.10
  • Ubuntu 17.04
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS


USN-3477-1 caused a regression in Firefox.

Software description

  • firefox - Mozilla Open Source web browser


USN-3477-1 fixed vulnerabilities in Firefox. The update caused search
suggestions to not be displayed when performing Google searches from the
search bar. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

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, read uninitialized
memory, obtain sensitive information, bypass same-origin restrictions,
bypass CSP protections, bypass mixed content blocking, spoof the
addressbar, or execute arbitrary code. (CVE-2017-7826, CVE-2017-7827,
CVE-2017-7828, CVE-2017-7830, CVE-2017-7831, CVE-2017-7832, CVE-2017-7833,
CVE-2017-7834, CVE-2017-7835, CVE-2017-7837, CVE-2017-7838, CVE-2017-7842)

It was discovered that javascript: URLs pasted in to the addressbar
would be executed instead of being blocked in some circumstances. If a
user were tricked in to copying a specially crafted URL in to the
addressbar, an attacker could potentially exploit this to conduct
cross-site scripting (XSS) attacks. (CVE-2017-7839)

It was discovered that exported bookmarks do not strip script elements
from user-supplied tags. If a user were tricked in to adding specially
crafted tags to bookmarks, exporting them and then opening the resulting
HTML file, an attacker could potentially exploit this to conduct
cross-site scripting (XSS) attacks. (CVE-2017-7840)

Update instructions

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

Ubuntu 17.10:
firefox 57.0+build4-0ubuntu0.17.10.6
Ubuntu 17.04:
firefox 57.0+build4-0ubuntu0.17.04.6
Ubuntu 16.04 LTS:
firefox 57.0+build4-0ubuntu0.16.04.6
Ubuntu 14.04 LTS:
firefox 57.0+build4-0ubuntu0.14.04.5

To update your system, please follow these instructions:

After a standard system update you need to restart Firefox to make
all the necessary changes.


LP: 1733970