CVE-2020-26951

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.

CVSS v3.0 6.1 MEDIUM
CVSS v2.0 4.3 MEDIUM

6.1^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://www.mozilla.org/security/advisories/mfsa2020-50/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-51/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-52/	Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1667113	Issue Tracking Permissions Required Vendor Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:firefox_esr::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::

Information

Published : 2020-12-08 17:15

Updated : 2020-12-09 11:49

NVD link : CVE-2020-26951

Mitre link : CVE-2020-26951

JSON object : View

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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Products Affected

mozilla

firefox
firefox_esr
thunderbird

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