CVE-2021-23953
4.3 · MEDIUMOverview
CVE-2021-23953 is a medium-severity vulnerability affecting mozilla firefox. It was published on February 26, 2021 and has a CVSS 3.1 base score of 4.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
If a user clicked into a specifically crafted PDF, the PDF reader could be confused into leaking cross-origin information, when said information is served as chunked data. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
Remediation
Check the references section for vendor advisories and patches from mozilla. Update firefox to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mozilla | firefox | >= 0, < 85.0 | Affected |
| mozilla | firefox_esr | >= 0, < 78.7 | Affected |
| mozilla | thunderbird | >= 0, < 78.7 | Affected |
References
Frequently Asked Questions
What is CVE-2021-23953?
CVE-2021-23953 is a medium-severity vulnerability affecting mozilla firefox. It was published on February 26, 2021 and has a CVSS 3.1 base score of 4.3 (MEDIUM).
How severe is CVE-2021-23953?
This vulnerability has a CVSS 3.1 base score of 4.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-23953?
Check the references section for vendor advisories and patches from mozilla. Update firefox to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-23953?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-23953 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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