CVE-2017-7816
WebExtensions could use popups and panels in the extension UI to load an "about:" privileged URL, violating security checks that disallow this behavior.
Does this matter?
Lower severity and a low EPSS score (1.23%). Track it; it rarely justifies an emergency change on its own.
Description
WebExtensions could use popups and panels in the extension UI to load an "about:" privileged URL, violating security checks that disallow this behavior. This vulnerability affects Firefox < 56.
- CVSS 3.0
- 5.3 MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- EPSS
- 1.23% probability · 69th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- mozilla/firefox
- Source
- security@mozilla.org
EPSS 1.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
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=1380597Exploit, 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=1380597Exploit, Issue Tracking
- https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.