CVE-2025-1018: firefox — Fix

Description

The fullscreen notification is prematurely hidden when fullscreen is re-requested quickly by the user. This could have been leveraged to perform a potential spoofing attack. This vulnerability was fixed in Firefox 135 and Thunderbird 135.

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CVSS v3.1 Score

5.3

MEDIUM

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

Weakness Type (CWE)

CWE-1021 CWE-1021

Affected Products

Vendor	Product	Versions
mozilla	firefox	< 135.0
mozilla	thunderbird	131.0 — 135.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-07/ https://www.mozilla.org/security/advisories/mfsa2025-11/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1910818

Frequently Asked Questions

What is CVE-2025-1018? +

The fullscreen notification is prematurely hidden when fullscreen is re-requested quickly by the user. This could have been leveraged to perform a potential spoofing attack. This vulnerability was fixed in Firefox 135 and Thunderbird 135. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2025-1018? +

CVE-2025-1018 has a CVSS v3.1 score of 5.3 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-2025-1018? +

CVE-2025-1018 affects products from mozilla, specifically: firefox, thunderbird. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-1018? +

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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