CVE-2023-4581

CVE-2023-4581: vulnerability in Mozilla Firefox

XLL file extensions were downloadable without warnings

Published 11 Sep 2023 · Updated 18 Dec 2025

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3Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackepss 0.6%

Excel `.xll` add-in files did not have a blocklist entry in Firefox's executable blocklist which allowed them to be downloaded without any warning of their potential harm. This vulnerability affects Firefox < 117, Firefox ESR < 102.15, Firefox ESR < 115.2, Thunderbird < 102.15, and Thunderbird < 115.2.

Affected products

Mozilla · Firefox Mozilla · Firefox ESR Mozilla · Thunderbird

Related CVEs — Mozilla Firefox

In the same product, most dangerous first.

CVE-2016-9079HIGHCVE-2016-9079EPSS 87.4%KEV CVE-2019-11708CRITICALCVE-2019-11708EPSS 55.9%KEV CVE-2019-17026HIGHCVE-2019-17026EPSS 46.3%KEV CVE-2019-11707HIGHCVE-2019-11707EPSS 38.0%KEV CVE-2024-9680CRITICALCVE-2024-9680EPSS 23.2%KEV CVE-2022-26485HIGHCVE-2022-26485EPSS 14.3%KEV

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1843758 https://www.mozilla.org/security/advisories/mfsa2023-34/https://www.mozilla.org/security/advisories/mfsa2023-35/https://www.mozilla.org/security/advisories/mfsa2023-36/https://www.mozilla.org/security/advisories/mfsa2023-37/https://www.mozilla.org/security/advisories/mfsa2023-38/