CVE-2019-11730

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.

6.5

CVSS

Severity: Medium

CVSS 3.1 •

CVSS 2.0 •

EPSS 34.65% Top 5%

Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory gentoo.org Vendor Advisory gentoo.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org

Affected: Mozilla Firefox ESR

Affected: Mozilla Firefox

Affected: Mozilla Thunderbird

References

Link	Tags
https://www.mozilla.org/security/advisories/mfsa2019-21/	vendor advisory
https://www.mozilla.org/security/advisories/mfsa2019-22/	vendor advisory
https://www.mozilla.org/security/advisories/mfsa2019-23/	vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1558299	issue tracking permissions required
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00055.html	vendor advisory mailing list third party advisory
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00058.html	vendor advisory mailing list third party advisory
https://lists.debian.org/debian-lts-announce/2019/08/msg00001.html	third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2019/08/msg00002.html	third party advisory mailing list
https://security.gentoo.org/glsa/201908-12	third party advisory vendor advisory
https://security.gentoo.org/glsa/201908-20	third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00073.html	vendor advisory mailing list third party advisory
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.html	vendor advisory mailing list third party advisory
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.html	vendor advisory mailing list third party advisory

Frequently Asked Questions

What is the severity of CVE-2019-11730?: CVE-2019-11730 has been scored as a medium severity vulnerability.
How to fix CVE-2019-11730?: To fix CVE-2019-11730, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-11730 being actively exploited in the wild?: It is possible that CVE-2019-11730 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~35% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-11730?: CVE-2019-11730 affects Mozilla Firefox ESR, Mozilla Firefox, Mozilla Thunderbird.