CVE-2018-5166

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-06-11 · updated 2026-06-17
Weakness: CWE-269

Description

WebExtensions can use request redirection and a "filterReponseData" filter to bypass host permission settings to redirect network traffic and access content from a host for which they do not have explicit user permission. This vulnerability affects Firefox < 60.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 17.10, 18.04
Mozilla Firefox: before 60.0 — fixed in 60.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 60.0. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/104139
http://www.securitytracker.com/id/1040896
https://bugzilla.mozilla.org/show_bug.cgi?id=1437325
https://usn.ubuntu.com/3645-1/
https://www.mozilla.org/security/advisories/mfsa2018-11/
http://www.securityfocus.com/bid/104139
http://www.securitytracker.com/id/1040896
https://bugzilla.mozilla.org/show_bug.cgi?id=1437325
https://usn.ubuntu.com/3645-1/
https://www.mozilla.org/security/advisories/mfsa2018-11/

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