CVE-2020-26951: XSS

Published Nov 17, 2020
·
Updated

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.

Other sources

A parsing and event loading mismatch in Thunderbird'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.

Mozilla

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<78.5
78.5
Mozilla Firefox<83.0
Mozilla Firefox ESR<78.5
Mozilla Thunderbird<78.5
Mozilla Firefox<83
83
Mozilla Firefox ESR<78.5
78.5

Event History

Nov 17, 2020
CVE Published
12:00 AM
Dec 9, 2020
CVE Published
via MITRE·12:19 AM
Data Sourced
via MITRE·12:19 AM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2020-26951?

CVE-2020-26951 is a vulnerability in Thunderbird's SVG code that could allow load events to fire, even after sanitization.

2

What software is affected by CVE-2020-26951?

CVE-2020-26951 affects Mozilla Firefox ESR versions up to 78.5, Mozilla Thunderbird version up to 78.5, and Mozilla Firefox versions up to 83.

3

How severe is CVE-2020-26951?

CVE-2020-26951 has a severity rating of 7 (high).

4

How can an attacker exploit CVE-2020-26951?

An attacker who can exploit an XSS vulnerability in privileged internal pages can use CVE-2020-26951 to bypass the built-in sanitizer.

5

What is the CWE classification of CVE-2020-26951?

CVE-2020-26951 is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation).

Contact

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