CVE-2024-9394: firefox XSS — Fix

Description

An attacker could, via a specially crafted multipart response, execute arbitrary JavaScript under the `resource://devtools` origin. This could allow them to access cross-origin JSON content. This access is limited to "same site" documents by the Site Isolation feature on desktop clients, but full cross-origin access is possible on Android versions. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Firefox ESR < 115.16, Thunderbird < 128.3, and Thunderbird < 131.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
mozilla	firefox	< 131.0
mozilla	firefox_esr	< 115.16.0
mozilla	firefox_esr	116.0 — 128.3.0
mozilla	thunderbird	< 128.3
mozilla	thunderbird	All
mozilla	thunderbird	All
mozilla	thunderbird	All
mozilla	thunderbird	All
mozilla	thunderbird	All
mozilla	thunderbird	All

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2024-46/ https://www.mozilla.org/security/advisories/mfsa2024-47/ https://www.mozilla.org/security/advisories/mfsa2024-48/ https://www.mozilla.org/security/advisories/mfsa2024-49/ https://www.mozilla.org/security/advisories/mfsa2024-50/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1918874 https://lists.debian.org/debian-lts-announce/2024/10/msg00004.html https://lists.debian.org/debian-lts-announce/2024/10/msg00006.html

Frequently Asked Questions

What is CVE-2024-9394? +

An attacker could, via a specially crafted multipart response, execute arbitrary JavaScript under the `resource://devtools` origin. This could allow them to access cross-origin JSON content. This access is limited to "same site" documents by the Site Isolation feature on desktop clients, but full cross-origin access is possible on Android versions. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Firefox ESR < 115.16, Thunderbird < 128.3, and Thunderbird < 131. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-9394? +

CVE-2024-9394 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-9394? +

CVE-2024-9394 affects products from mozilla, specifically: firefox, firefox_esr, thunderbird. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-9394? +

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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CVE-2024-9394