CVE-2021-43818
8.2 · HIGHOverview
CVE-2021-43818 is a high-severity vulnerability affecting lxml lxml. It was published on December 13, 2021 and has a CVSS 3.1 base score of 8.2 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.2, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
lxml is a library for processing XML and HTML in the Python language. Prior to version 4.6.5, the HTML Cleaner in lxml.html lets certain crafted script content pass through, as well as script content in SVG files embedded using data URIs. Users that employ the HTML cleaner in a security relevant context should upgrade to lxml 4.6.5 to receive a patch. There are no known workarounds available.
Remediation
Check the references section for vendor advisories and patches from lxml. Update lxml 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 |
|---|---|---|---|
| lxml | lxml | >= 0, < 4.6.5 | Affected |
References
Frequently Asked Questions
What is CVE-2021-43818?
CVE-2021-43818 is a high-severity vulnerability affecting lxml lxml. It was published on December 13, 2021 and has a CVSS 3.1 base score of 8.2 (HIGH).
How severe is CVE-2021-43818?
This vulnerability has a CVSS 3.1 base score of 8.2, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-43818?
Check the references section for vendor advisories and patches from lxml. Update lxml 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-2021-43818?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-43818 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.
Automated penetration testing that runs continuously, not just quarterly.
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