Vulnerability in Mozilla Firefox
CVE-2019-11730
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.203 (97.4th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.203 · newest: 0.203 · change: 0.000
Affected products
- Mozilla Firefox — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Firefox Esr
- Mozilla Thunderbird — versions unspecified
- Debian Linux — versions 8.0
- openSUSE Leap — versions 15.0, 15.1
- SUSE Linux Enterprise — versions 12.0
- SUSE Package Hub
Public proof-of-concept exploits
References
- www.mozilla.org/security/advisories/mfsa2019-21/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2019-22/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2019-23/ (Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
- lists.opensuse.org/opensuse-security-announce/2019-07/msg00055.html (vendor-advisory, Mailing List, Third Party Advisory)
- lists.opensuse.org/opensuse-security-announce/2019-07/msg00058.html (vendor-advisory, Mailing List, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2019/08/msg00001.html (mailing-list, Mailing List, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2019/08/msg00002.html (mailing-list, Mailing List, Third Party Advisory)
- security.gentoo.org/glsa/201908-12 (vendor-advisory, Third Party Advisory)
- security.gentoo.org/glsa/201908-20 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-11730?
- CVE-2019-11730 is a medium-severity vulnerability in Mozilla Firefox. CVSS score: 6.5/10. Published 2019-07-23.
- How severe is CVE-2019-11730?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2019-11730 known to be exploited?
- 19 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.