CVE-2017-7821

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-06-11 · updated 2026-06-17
Weakness: CWE-732

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.

Affected products

Mozilla Firefox: through 55.0.3

References

http://www.securityfocus.com/bid/101057
http://www.securitytracker.com/id/1039465
https://bugzilla.mozilla.org/show_bug.cgi?id=1346515
https://www.mozilla.org/security/advisories/mfsa2017-21/
http://www.securityfocus.com/bid/101057
http://www.securitytracker.com/id/1039465
https://bugzilla.mozilla.org/show_bug.cgi?id=1346515
https://www.mozilla.org/security/advisories/mfsa2017-21/

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