SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

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.

MEDIUM 6.5EPSS 20.3%

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
CISA KEV
Not listed
Affected
mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird · debian/debian linux · opensuse/leap · suse/package hub
Source
security@mozilla.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.