CVE-2021-37700
MEDIUM@github/paste-markdown < 0.3.4 - Stored Cross-Site Scripting via Clipboard Table Element Handling
Title source: llmDescription
@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.
References (4)
Core 4
Core References
Exploit, Third Party Advisory x_refsource_confirm
https://github.com/github/paste-markdown/security/advisories/GHSA-gpfj-4j6g-c4w9
Patch, Third Party Advisory x_refsource_misc
https://github.com/github/paste-markdown/commit/32b7ea3f29ae8f256f9d19768387be42678ddf30
Release Notes, Third Party Advisory x_refsource_misc
https://github.com/github/paste-markdown/releases/tag/v0.3.4
Various Sources x_refsource_misc
https://www.npmjs.com/package/%40github/paste-markdown
Scores
CVSS v3
6.5
EPSS
0.0166
EPSS Percentile
73.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Details
CWE
CWE-79
Status
published
Products (2)
github/paste-markdown
0 - 0.3.4npm
paste-markdown_project/paste-markdown
< 0.3.4
Published
Aug 12, 2021
Tracked Since
Feb 18, 2026