CVE-2025-5020

Description

Opening maliciously-crafted URLs in Firefox from other apps such as Safari could have allowed attackers to spoof website addresses if the URLs utilized non-HTTP schemes used internally by the Firefox iOS client. This vulnerability was fixed in Firefox for iOS 139.

CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Weakness Type (CWE)

CWE-939 CWE-939

Affected Products

Vendor	Product	Versions
mozilla	firefox	< 139.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-39/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1951558

Frequently Asked Questions

What is CVE-2025-5020? +

Opening maliciously-crafted URLs in Firefox from other apps such as Safari could have allowed attackers to spoof website addresses if the URLs utilized non-HTTP schemes used internally by the Firefox iOS client. This vulnerability was fixed in Firefox for iOS 139. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2025-5020? +

CVE-2025-5020 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-5020? +

CVE-2025-5020 affects products from mozilla, specifically: firefox. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-5020? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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