CVE-2020-26293

HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks. In HtmlSanitizer before version 5.0.372, there is a possible XSS bypass if style tag is allowed. If you have explicitly allowed the `<style>` tag, an attacker could craft HTML that includes script after passing through the sanitizer. The default settings disallow the `<style>` tag so there is no risk if you have not explicitly allowed the `<style>` tag. The problem has been fixed in version 5.0.372.

CVSS v3 6.1 MEDIUM
CVSS v2.0 4.3 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://github.com/mganss/HtmlSanitizer/commit/a3a7602a44d4155d51ec0fbbedc2a49e9c7e2eb8	Patch Third Party Advisory
https://github.com/mganss/HtmlSanitizer/releases/tag/v5.0.372	Release Notes Third Party Advisory
https://github.com/mganss/HtmlSanitizer/security/advisories/GHSA-8j9v-h2vp-2hhv	Third Party Advisory
https://www.nuget.org/packages/HtmlSanitizer/	Product Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:htmlsanitizer_project:htmlsanitizer:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2021-01-04 19:15

Updated : 2021-01-07 20:29

NVD link : CVE-2020-26293

Mitre link : CVE-2020-26293

CVE.ORG link : CVE-2020-26293

JSON object : View

Products Affected

htmlsanitizer_project

htmlsanitizer

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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