Apostrophe Technologies sanitize-html before 2.3.2 does not properly validate the hostnames set by the "allowedIframeHostnames" option when the "allowIframeRelativeUrls" is set to true, which allows attackers to bypass hostname whitelist for iframe element, related using an src value that starts with "/\\example.com".
CVE-2021-26540 - Medium Severity Vulnerability
Vulnerable Library - sanitize-html-1.26.0.tgz
Clean up user-submitted HTML, preserving whitelisted elements and whitelisted attributes on a per-element basis
Library home page: https://registry.npmjs.org/sanitize-html/-/sanitize-html-1.26.0.tgz
Path to dependency file: /node_modules/sanitize-html/package.json
Path to vulnerable library: /node_modules/sanitize-html/package.json
Dependency Hierarchy: - :x: **sanitize-html-1.26.0.tgz** (Vulnerable Library)
Found in HEAD commit: 0c22b39b4f64e2bf88c2b59e4e09bc0b140c91e6
Found in base branch: develop
Vulnerability Details
Apostrophe Technologies sanitize-html before 2.3.2 does not properly validate the hostnames set by the "allowedIframeHostnames" option when the "allowIframeRelativeUrls" is set to true, which allows attackers to bypass hostname whitelist for iframe element, related using an src value that starts with "/\\example.com".
Publish Date: 2021-02-08
URL: CVE-2021-26540
CVSS 3 Score Details (5.3)
Base Score Metrics: - Exploitability Metrics: - Attack Vector: Network - Attack Complexity: Low - Privileges Required: None - User Interaction: None - Scope: Unchanged - Impact Metrics: - Confidentiality Impact: None - Integrity Impact: Low - Availability Impact: None
For more information on CVSS3 Scores, click here.Suggested Fix
Type: Upgrade version
Origin: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-26540
Release Date: 2021-02-08
Fix Resolution: 2.3.2