CVE-2021-43818— HTML Cleaner allows crafted and SVG embedded scripts to pass through
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I. Basic Information for CVE-2021-43818
Vulnerability Information
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Vulnerability Title
HTML Cleaner allows crafted and SVG embedded scripts to pass through
Source: NVD (National Vulnerability Database)
Vulnerability 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.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N
Source: NVD (National Vulnerability Database)
Vulnerability Type
输出中的特殊元素转义处理不恰当(注入)
Source: NVD (National Vulnerability Database)
Vulnerability Title
lxml 注入漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
lxml是lxml个人开发者的一个可与Python交互用于定位Html中元素的软件。 lxml 4.6.5之前版本存在注入漏洞，该漏洞源于HTML Cleaner允许某些精心制作的脚本内容以及使用数据URI嵌入的SVG文件中的脚本内容通过。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2021-43818
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- https://security.netapp.com/advisory/ntap-20220107-0005/x_refsource_CONFIRM
- https://github.com/lxml/lxml/security/advisories/GHSA-55x5-fj6c-h6m8x_refsource_CONFIRM
- https://www.oracle.com/security-alerts/cpujul2022.htmlx_refsource_MISC
- https://www.oracle.com/security-alerts/cpuapr2022.htmlx_refsource_MISC
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZQ4SPKJX3RRJK4UWA6FXCRHD2TVRQI44/vendor-advisoryx_refsource_FEDORA
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/V2XMOM5PFT6U5AAXY6EFNT5JZCKKHK2V/vendor-advisoryx_refsource_FEDORA
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WZGNET2A4WGLSUXLBFYKNC5PXHQMI3I7/vendor-advisoryx_refsource_FEDORA
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TUIS2KE3HZ2AAQKXFLTJFZPP2IFHJTC7/vendor-advisoryx_refsource_FEDORA
- https://nvd.nist.gov/vuln/detail/CVE-2021-43818
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V. Comments for CVE-2021-43818
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