CVE-2020-12400

Name: CVE-2020-12400
Creator: NVD / NIST
Published: 2020-10-08T14:15:11.17+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.7/10EPSS 0.26%

Last modified Jun 17, 2026

CVE-2020-12400 is a medium-severity vulnerability rated 4.7/10 on the CVSS scale. When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack. This vulnerability affects Firefox < 80 and Firefox for Android < 80.. EPSS estimates a 0.26% chance of exploitation in the next 30 days.

Description

When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack. This vulnerability affects Firefox < 80 and Firefox for Android < 80.

Metrics

CVSS 3.1

4.7/10

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

EPSS Probability

0.26%

17.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-203

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 80.0

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1623116Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html
https://www.mozilla.org/security/advisories/mfsa2020-36/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-39/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1623116Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html
https://www.mozilla.org/security/advisories/mfsa2020-36/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-39/Vendor Advisory

Timeline

Published: Oct 8, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-12400?

How severe is CVE-2020-12400?

CVE-2020-12400 has a CVSS score of 4.7/10 (MEDIUM severity). The EPSS model estimates a 0.26% probability of exploitation in the next 30 days.

How do I fix CVE-2020-12400?

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-2020-12400?

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

Scan your code now

Source: NVD / NIST