Mermaid is a JavaScript based diagramming and charting tool that uses Markdown-inspired text definitions and a renderer to create and modify complex diagrams. An attacker is able to inject arbitrary `CSS` into the generated graph allowing them to change the styling of elements outside of the generated graph, and potentially exfiltrate sensitive information by using specially crafted `CSS` selectors. The following example shows how an attacker can exfiltrate the contents of an input field by bruteforcing the `value` attribute one character at a time. Whenever there is an actual match, an `http` request will be made by the browser in order to "load" a background image that will let an attacker know what's the value of the character. This issue may lead to `Information Disclosure` via CSS selectors and functions able to generate HTTP requests. This also allows an attacker to change the document in ways which may lead a user to perform unintended actions, such as clicking on a link, etc. This issue has been resolved in version 9.1.3. Users are advised to upgrade. Users unable to upgrade should ensure that user input is adequately escaped before embedding it in CSS blocks.
CVE-2022-31108 - Medium Severity Vulnerability
Markdownish syntax for generating flowcharts, sequence diagrams, class diagrams, gantt charts and git graphs.
Library home page: https://registry.npmjs.org/mermaid/-/mermaid-8.13.3.tgz
Path to dependency file: /package.json
Path to vulnerable library: /node_modules/mermaid/package.json
Dependency Hierarchy: - :x: **mermaid-8.13.3.tgz** (Vulnerable Library)
Found in HEAD commit: 5a07ad71010693de12293f5ff1fadc890259b5e0
Found in base branch: main
Mermaid is a JavaScript based diagramming and charting tool that uses Markdown-inspired text definitions and a renderer to create and modify complex diagrams. An attacker is able to inject arbitrary `CSS` into the generated graph allowing them to change the styling of elements outside of the generated graph, and potentially exfiltrate sensitive information by using specially crafted `CSS` selectors. The following example shows how an attacker can exfiltrate the contents of an input field by bruteforcing the `value` attribute one character at a time. Whenever there is an actual match, an `http` request will be made by the browser in order to "load" a background image that will let an attacker know what's the value of the character. This issue may lead to `Information Disclosure` via CSS selectors and functions able to generate HTTP requests. This also allows an attacker to change the document in ways which may lead a user to perform unintended actions, such as clicking on a link, etc. This issue has been resolved in version 9.1.3. Users are advised to upgrade. Users unable to upgrade should ensure that user input is adequately escaped before embedding it in CSS blocks.
Publish Date: 2022-06-28
URL: CVE-2022-31108
Base Score Metrics: - Exploitability Metrics: - Attack Vector: Network - Attack Complexity: Low - Privileges Required: None - User Interaction: Required - Scope: Changed - Impact Metrics: - Confidentiality Impact: Low - Integrity Impact: Low - Availability Impact: None
For more information on CVSS3 Scores, click here.Type: Upgrade version
Origin: https://github.com/mermaid-js/mermaid/security/advisories/GHSA-x3vm-38hw-55wf
Release Date: 2022-06-28
Fix Resolution: 9.1.3
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