CVE-2021-21236— Regular Expression Denial of Service in CairoSVG
Quick assessment
Affected
Kozea CairoSVG
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Kozea CairoSVG是Kozea社区的一个基于Python可将SVG文件转换为为PDF，EPS，PS和PNG文件的软件。 CairoSVG 2.5.1之前版本存在资源管理错误漏洞，攻击者可利用该漏洞提供恶意的SVG，导致程序很长一段时间内无法处理该文件。
Possible ATT&CK Techniques 1 AI
T1496 · Resource Hijacking
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I. Basic Information for CVE-2021-21236
Vulnerability Information
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Vulnerability Title
Regular Expression Denial of Service in CairoSVG
Source: CVE Program / CVE List V5
Vulnerability Description
CairoSVG is a Python (pypi) package. CairoSVG is an SVG converter based on Cairo. In CairoSVG before version 2.5.1, there is a regular expression denial of service (REDoS) vulnerability. When processing SVG files, the python package CairoSVG uses two regular expressions which are vulnerable to Regular Expression Denial of Service (REDoS). If an attacker provides a malicious SVG, it can make cairosvg get stuck processing the file for a very long time. This is fixed in version 2.5.1. See Referenced GitHub advisory for more information.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
未加控制的资源消耗(资源穷尽)
Source: CVE Program / CVE List V5
Vulnerability Title
Kozea CairoSVG 资源管理错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Kozea CairoSVG是Kozea社区的一个基于Python可将SVG文件转换为为PDF，EPS，PS和PNG文件的软件。 CairoSVG 2.5.1之前版本存在资源管理错误漏洞，攻击者可利用该漏洞提供恶意的SVG，导致程序很长一段时间内无法处理该文件。
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-2021-21236
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Patches & Fixes for CVE-2021-21236 (1)
Vendor Advisories for CVE-2021-21236 (1)
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https://github.com/Kozea/CairoSVG/security/advisories/GHSA-hq37-853p-g5cf x_refsource_CONFIRM
Other References for CVE-2021-21236 (2)
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https://github.com/Kozea/CairoSVG/releases/tag/2.5.1 x_refsource_MISC
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https://pypi.org/project/CairoSVG/ x_refsource_MISC
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V. Comments for CVE-2021-21236
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