CVE-2021-23974: XSS
The DOMParser API did not properly process '<noscript>' elements for escaping. This could be used as an mXSS vector to bypass an HTML Sanitizer. This vulnerability affects Firefox < 86.
Other sources
The DOMParser API did not properly process <noscript> elements for escaping. This could be used as an mXSS vector to bypass an HTML Sanitizer.
— Mozilla
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Firefoxto a version that resolves this vulnerability.Fixed in 86 - Upgrade
Upgrade
alpine/firefoxto a version that resolves this vulnerability.Fixed in 87.0-r0 - Upgrade
Upgrade
alpine/librewolfto a version that resolves this vulnerability.Fixed in 87.0-r0
Event History
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
What is the severity of CVE-2021-23974?
CVE-2021-23974 has been classified as a moderate severity vulnerability.
How do I fix CVE-2021-23974?
To fix CVE-2021-23974, update your Firefox browser to version 86 or later.
Which versions of Firefox are affected by CVE-2021-23974?
CVE-2021-23974 affects Firefox versions earlier than 86.
What type of vulnerability is CVE-2021-23974?
CVE-2021-23974 is a reflected Cross-Site Scripting (mXSS) vulnerability.
Can CVE-2021-23974 be exploited easily?
Yes, CVE-2021-23974 can be exploited to bypass an HTML sanitizer, making it a potential attack vector.