CVE-2025-0237: firefox Auth Bypass — Fix

Description

The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.

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CVSS v3.1 Score

5.4

MEDIUM

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

Weakness Type (CWE)

CWE-863 Incorrect Authorization

Affected Products

Vendor	Product	Versions
mozilla	firefox	< 128.6.0
mozilla	firefox	< 134.0
mozilla	thunderbird	< 128.6.0
mozilla	thunderbird	129.0 — 134.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-01/ https://www.mozilla.org/security/advisories/mfsa2025-02/ https://www.mozilla.org/security/advisories/mfsa2025-04/ https://www.mozilla.org/security/advisories/mfsa2025-05/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1915257 https://lists.debian.org/debian-lts-announce/2025/01/msg00004.html

Frequently Asked Questions

What is CVE-2025-0237? +

The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2025-0237? +

CVE-2025-0237 has a CVSS v3.1 score of 5.4 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-2025-0237? +

CVE-2025-0237 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-2025-0237? +

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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