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.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 20.3%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
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.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- EPSS
- 20.27% probability · 97th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird · debian/debian linux · opensuse/leap · suse/package hub
- Source
- security@mozilla.org
EPSS 20.3% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00055.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00058.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00073.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.htmlMailing List, Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1558299Issue Tracking, Permissions Required
- https://lists.debian.org/debian-lts-announce/2019/08/msg00001.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2019/08/msg00002.htmlMailing List, Third Party Advisory
- https://security.gentoo.org/glsa/201908-12Third Party Advisory
- https://security.gentoo.org/glsa/201908-20Third Party Advisory
- 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
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00055.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00058.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00073.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.htmlMailing List, Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1558299Issue Tracking, Permissions Required
- https://lists.debian.org/debian-lts-announce/2019/08/msg00001.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2019/08/msg00002.htmlMailing List, Third Party Advisory
- https://security.gentoo.org/glsa/201908-12Third Party Advisory
- https://security.gentoo.org/glsa/201908-20Third Party Advisory
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.