CVE-2020-12418

Name: CVE-2020-12418
Creator: NVD / NIST
Published: 2020-07-09T15:15:11.817+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 3.03%

Last modified Jun 17, 2026

CVE-2020-12418 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Manipulating individual parts of a URL object could have caused an out-of-bounds read, leaking process memory to malicious JavaScript. This vulnerability affects Firefox ESR < 68.10, Firefox < 78, and Thunderbird < 68.10.0.. EPSS estimates a 3.03% chance of exploitation in the next 30 days.

Description

Manipulating individual parts of a URL object could have caused an out-of-bounds read, leaking process memory to malicious JavaScript. This vulnerability affects Firefox ESR < 68.10, Firefox < 78, and Thunderbird < 68.10.0.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

3.03%

85.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-125

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 78.0
Mozilla	Firefox Esr	< 68.10
Mozilla	Thunderbird	< 68.10.0
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	19.10
Canonical	Ubuntu Linux	20.04
Opensuse	Leap	15.1
Opensuse	Leap	15.2

References

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00023.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00026.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.htmlMailing List, Third Party Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1641303Issue Tracking, Permissions Required, Vendor Advisory
https://security.gentoo.org/glsa/202007-09Third Party Advisory
https://security.gentoo.org/glsa/202007-10Third Party Advisory
https://usn.ubuntu.com/4421-1/Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-24/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-25/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-26/Vendor Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00023.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00026.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.htmlMailing List, Third Party Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1641303Issue Tracking, Permissions Required, Vendor Advisory
https://security.gentoo.org/glsa/202007-09Third Party Advisory
https://security.gentoo.org/glsa/202007-10Third Party Advisory
https://usn.ubuntu.com/4421-1/Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-24/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-25/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-26/Vendor Advisory

Timeline

Published: Jul 9, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-12418?

How severe is CVE-2020-12418?

CVE-2020-12418 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 3.03% probability of exploitation in the next 30 days.

How do I fix CVE-2020-12418?

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-2020-12418?

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

Scan your code now

Source: NVD / NIST