CVE-2017-7821

Name: CVE-2017-7821
Creator: NVD / NIST
Published: 2018-06-11T21:29:10.92+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 1.98%

Last modified Jun 17, 2026

CVE-2017-7821 is a vulnerability of currently unknown severity. A vulnerability where WebExtensions can download and attempt to open a file of some non-executable file types. This can be triggered without specific user interaction for the file download and open actions. EPSS estimates a 1.98% chance of exploitation in the next 30 days.

Description

A vulnerability where WebExtensions can download and attempt to open a file of some non-executable file types. This can be triggered without specific user interaction for the file download and open actions. This could be used to trigger known vulnerabilities in the programs that handle those document types. This vulnerability affects Firefox < 56.

Metrics

EPSS Probability

1.98%

78.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-732

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	<= 55.0.3

References

http://www.securityfocus.com/bid/101057Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1039465Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1346515Exploit, Issue Tracking
https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory
http://www.securityfocus.com/bid/101057Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1039465Third Party Advisory, VDB Entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1346515Exploit, Issue Tracking
https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory

Timeline

Published: Jun 11, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2017-7821?

How severe is CVE-2017-7821?

Severity scoring for CVE-2017-7821 is pending analysis. The EPSS model estimates a 1.98% probability of exploitation in the next 30 days.

How do I fix CVE-2017-7821?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2017-7821?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST