CVE-2021-37700: @github/paste-markdown is an npm package for pasting markdown objects

This month

MEDIUM 6.5UPGRADE

CVE-2021-37700 is a medium-severity flaw (CVSS 6.5) affecting paste-markdown. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

@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 t

Why this priority

Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	1.7% (top 23%)
CISA exploited list	No
Weakness	CWE-79
Published	2021-08-12
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: paste-markdown project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-08-12 21:15 UTCPublished CVE record published
2026-06-17 04:01 UTCUpdated Record last modified

paste-markdown project paste-markdown UPGRADE

Affected: < 0.3.4

Fixed in: 0.3.4

Safe to downgrade to: no unaffected older release

1. Check installed version

npm ls paste-markdown

2. UPGRADE to 0.3.4

npm install paste-markdown@">=0.3.4"

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-37700?

paste-markdown: upgrade to 0.3.4. Exact commands for each OS are on this page.

Is CVE-2021-37700 being exploited?

CVE-2021-37700 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-37700 affect?

CVE-2021-37700 affects paste-markdown. Severity is medium (CVSS 6.5). @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 dy

How urgent is CVE-2021-37700?

Priority 47/100. Public exploit reference

Software pages

GitHub vulnerabilities · npm packages vulnerabilities

References

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