CVE-2020-26951

MediumCVSS 6.1/10Last modified Jun 17, 2026

Description

A parsing and event loading mismatch in Firefox's SVG code could have allowed load events to fire, even after sanitization. An attacker already capable of exploiting an XSS vulnerability in privileged internal pages could have used this attack to bypass our built-in sanitizer. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Metrics

CVSS 3.1 6.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness enumeration

CWE-79

Affected software

No affected versions have been published.

Timeline

Published: Dec 9, 2020
Last modified: Jun 17, 2026
NVD status: Modified

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