CVE-2025-8029: firefox — Fix

Description

Thunderbird executed `javascript:` URLs when used in `object` and `embed` tags. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

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CVSS v3.1 Score

8.1

HIGH

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

Weakness Type (CWE)

CWE-80 CWE-80

Affected Products

Vendor	Product	Versions
mozilla	firefox	< 128.13.0
mozilla	firefox	< 141.0
mozilla	firefox	140.0 — 140.1.0
mozilla	thunderbird	< 128.13.0
mozilla	thunderbird	< 141.0
mozilla	thunderbird	140.0 — 140.1.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-56/ https://www.mozilla.org/security/advisories/mfsa2025-58/ https://www.mozilla.org/security/advisories/mfsa2025-59/ https://www.mozilla.org/security/advisories/mfsa2025-61/ https://www.mozilla.org/security/advisories/mfsa2025-62/ https://www.mozilla.org/security/advisories/mfsa2025-63/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1928021 https://lists.debian.org/debian-lts-announce/2025/07/msg00016.html

Frequently Asked Questions

What is CVE-2025-8029? +

Thunderbird executed `javascript:` URLs when used in `object` and `embed` tags. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2025-8029? +

CVE-2025-8029 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-8029? +

CVE-2025-8029 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-2025-8029? +

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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