CVE-2021-34817

Name: CVE-2021-34817
Creator: NVD / NIST
Published: 2021-07-19T14:15:08.15+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 1.34%

Last modified Jun 17, 2026

CVE-2021-34817 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. A Cross-Site Scripting (XSS) issue in the chat component of Etherpad 1.8.13 allows remote attackers to inject arbitrary JavaScript or HTML by importing a crafted pad.. EPSS estimates a 1.34% chance of exploitation in the next 30 days.

Description

A Cross-Site Scripting (XSS) issue in the chat component of Etherpad 1.8.13 allows remote attackers to inject arbitrary JavaScript or HTML by importing a crafted pad.

Metrics

CVSS 3.1

6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

1.34%

67.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Etherpad	Etherpad	1.8.13

References

https://blog.sonarsource.com/etherpad-code-execution-vulnerabilitiesThird Party Advisory
https://etherpad.org/#downloadPatch, Vendor Advisory
https://github.com/ether/etherpad-lite/commit/a7968115581e20ef47a533e030f59f830486bdfaExploit, Patch, Third Party Advisory
https://github.com/ether/etherpad-lite/releases/tag/1.8.14Patch, Release Notes, Third Party Advisory
https://blog.sonarsource.com/etherpad-code-execution-vulnerabilitiesThird Party Advisory
https://etherpad.org/#downloadPatch, Vendor Advisory
https://github.com/ether/etherpad-lite/commit/a7968115581e20ef47a533e030f59f830486bdfaExploit, Patch, Third Party Advisory
https://github.com/ether/etherpad-lite/releases/tag/1.8.14Patch, Release Notes, Third Party Advisory

Timeline

Published: Jul 19, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-34817?

A Cross-Site Scripting (XSS) issue in the chat component of Etherpad 1.8.13 allows remote attackers to inject arbitrary JavaScript or HTML by importing a crafted pad.

How severe is CVE-2021-34817?

CVE-2021-34817 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 1.34% probability of exploitation in the next 30 days.

How do I fix CVE-2021-34817?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-34817?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST