#VU33439 Information disclosure
Vulnerability identifier: #VU33439
Vulnerability risk: Medium
CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-200
Exploitation vector: Network
Exploit availability: No
Description
The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.
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.
Mitigation
Install update from vendor's website.
External links
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00055.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00058.html
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00073.html
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.html
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.html
http://bugzilla.mozilla.org/show_bug.cgi?id=1558299
http://lists.debian.org/debian-lts-announce/2019/08/msg00001.html
http://lists.debian.org/debian-lts-announce/2019/08/msg00002.html
http://security.gentoo.org/glsa/201908-12
http://security.gentoo.org/glsa/201908-20
http://www.mozilla.org/security/advisories/mfsa2019-21/
http://www.mozilla.org/security/advisories/mfsa2019-22/
http://www.mozilla.org/security/advisories/mfsa2019-23/
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
