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Status published
Medium
CVE-2020-26956
In some cases, removing HTML elements during sanitization would keep...
Vulnerability Description
In some cases, removing HTML elements during sanitization would keep existing SVG event handlers and therefore lead to XSS. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
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Affected Vendor
Mozilla
View all reports →Affected Software
Firefox, Firefox ESR, Thunderbird
Vulnerable Versions:
< 83, < 78.5
Timeline
Official Publish:
December 9th, 2020
Last Modified:
August 4th, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.