CVE-2019-11730

Medium

Description

A vulnerability exists where if a user opens a locally saved HTML file, this file can use file: URIs to access other files in the same directory or sub-directories if the names are known or guessed. The Fetch API can then be used to read the contents of any files stored in these directories and they may uploaded to a server. It was demonstrated that in combination with a popular Android messaging app, if a malicious HTML attachment is sent to a user and they opened that attachment in Firefox, due to that app's predictable pattern for locally-saved file names, it is possible to read attachments the victim received from other correspondents. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

SeverityMedium
CVSS6.5
Exploit probability—
ProductMozilla Firefox
PublishedJul 23, 2019
First seenJul 23, 2019

How to fix

Update
  • mozilla firefox68.0 or later
  • mozilla firefox_esr60.8 or later
  • mozilla thunderbird60.8 or later

Affected products

ProductAffected versionsFixed in
mozilla firefoxv < 68.068.0
mozilla firefox_esrv < 60.860.8
mozilla thunderbirdv < 60.860.8
debian debian_linux8.0—
opensuse leap15.0, 15.1—
suse package_hubNo range specified—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.