CVE-2017-5420

Severity: medium (CVSS 6.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-06-11 · updated 2026-06-17
Weakness: CWE-20

Description

A "javascript:" url loaded by a malicious page can obfuscate its location by blanking the URL displayed in the addressbar, allowing for an attacker to spoof an existing page without the malicious page's address being displayed correctly. This vulnerability affects Firefox < 52.

Affected products

Mozilla Firefox: before 52.0 — fixed in 52.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 52.0. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/96692
http://www.securitytracker.com/id/1037966
https://bugzilla.mozilla.org/show_bug.cgi?id=1284395
https://www.mozilla.org/security/advisories/mfsa2017-05/
http://www.securityfocus.com/bid/96692
http://www.securitytracker.com/id/1037966
https://bugzilla.mozilla.org/show_bug.cgi?id=1284395
https://www.mozilla.org/security/advisories/mfsa2017-05/

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