CVE-2021-37700

Public Exploit
Clipboard-based DOM-XSS

Description

@github/paste-markdown is an npm package for pasting markdown objects. A self Cross-Site Scripting vulnerability exists in the @github/paste-markdown before version 0.3.4. If the clipboard data contains the string `<table>`, a **div** is dynamically created, and the clipboard content is copied into its **innerHTML** property without any sanitization, resulting in improper execution of JavaScript in the browser of the victim (the user who pasted the code). Users directed to copy text from a malicious website and paste it into pages that utilize this library are affected. This is fixed in version 0.3.4. Refer the to the referenced GitHub Advisory for more details including an example exploit.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.67% Top 30%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: github paste-markdown
Published at:
Updated at:

References

Link Tags
https://github.com/github/paste-markdown/security/advisories/GHSA-gpfj-4j6g-c4w9 third party advisory exploit
https://github.com/github/paste-markdown/commit/32b7ea3f29ae8f256f9d19768387be42678ddf30 third party advisory patch
https://github.com/github/paste-markdown/releases/tag/v0.3.4 third party advisory release notes
https://www.npmjs.com/package/%40github/paste-markdown

Frequently Asked Questions

What is the severity of CVE-2021-37700?
CVE-2021-37700 has been scored as a medium severity vulnerability.
How to fix CVE-2021-37700?
To fix CVE-2021-37700, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-37700 being actively exploited in the wild?
It is possible that CVE-2021-37700 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37700?
CVE-2021-37700 affects github paste-markdown.
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