CVE-2023-4581

Name: CVE-2023-4581
Creator: NVD / NIST
Published: 2023-09-11T09:15:09.55+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.3/10EPSS 0.50%

Last modified Jun 17, 2026

CVE-2023-4581 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. 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.. EPSS estimates a 0.50% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

4.3/10

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

EPSS Probability

0.50%

38.7th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 117.0
Mozilla	Firefox	>= 115.0, < 115.2
Mozilla	Firefox Esr	< 102.15
Mozilla	Thunderbird	< 115.2

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1843758Issue Tracking, Permissions Required
https://www.mozilla.org/security/advisories/mfsa2023-34/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-35/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-36/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-37/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-38/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1843758Issue Tracking, Permissions Required
https://www.mozilla.org/security/advisories/mfsa2023-34/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-35/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-36/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-37/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2023-38/Vendor Advisory

Timeline

Published: Sep 11, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-4581?

How severe is CVE-2023-4581?

CVE-2023-4581 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 0.50% probability of exploitation in the next 30 days.

How do I fix CVE-2023-4581?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-4581?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST