Arbitrary Code Injection Affecting lxml package, versions <4.7.1-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
2.48% (83rd percentile)

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  • Snyk IDSNYK-ECHOLATEST-LXML-19222760
  • published23 Aug 2026
  • disclosed13 Dec 2021

Introduced: 13 Dec 2021

CVE-2021-43818  (opens in a new tab)
CWE-74  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Echo:latest lxml to version 4.7.1-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream lxml package and not the lxml package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.

References

CVSS Base Scores

version 3.1