CVE-2020-15676

Description

Firefox sometimes ran the onload handler for SVG elements that the DOM sanitizer decided to remove, resulting in JavaScript being executed after pasting attacker-controlled data into a contenteditable element. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.26% Top 25%
Vendor Advisory debian.org Vendor Advisory gentoo.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-43/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-44/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-42/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1646140 issue tracking permissions required vendor advisory
https://www.debian.org/security/2020/dsa-4770 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00020.html third party advisory mailing list
https://security.gentoo.org/glsa/202010-02 third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00074.html mailing list broken link third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00077.html mailing list broken link third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-15676?
CVE-2020-15676 has been scored as a medium severity vulnerability.
How to fix CVE-2020-15676?
To fix CVE-2020-15676, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-15676 being actively exploited in the wild?
It is possible that CVE-2020-15676 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-15676?
CVE-2020-15676 affects Mozilla Firefox, Mozilla Thunderbird, Mozilla Firefox ESR.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.