CVE-2021-35240

Name: CVE-2021-35240
Creator: NVD / NIST
Published: 2021-08-31T16:15:07.863+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.8/10EPSS 1.07%

Last modified Jun 17, 2026

CVE-2021-35240 is a medium-severity vulnerability rated 4.8/10 on the CVSS scale. A security researcher stored XSS via a Help Server setting. This affects customers using Internet Explorer, because they do not support 'rel=noopener'.. EPSS estimates a 1.07% chance of exploitation in the next 30 days.

Description

A security researcher stored XSS via a Help Server setting. This affects customers using Internet Explorer, because they do not support 'rel=noopener'.

Metrics

CVSS 3.1

4.8/10

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

EPSS Probability

1.07%

60.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Solarwinds	Orion Platform	<= 2020.2.5

References

https://documentation.solarwinds.com/en/success_center/orionplatform/content/core-secure-configuration.htmProduct, Vendor Advisory
https://support.solarwinds.com/SuccessCenter/s/article/Mitigate-the-Stored-XSS-via-Help-Server-setting-CVE-2021-35240?language=en_USPatch, Vendor Advisory
https://support.solarwinds.com/SuccessCenter/s/article/Orion-Platform-2020-2-6-Hotfix-1?language=en_USMitigation, Vendor Advisory
https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35240Vendor Advisory
https://documentation.solarwinds.com/en/success_center/orionplatform/content/core-secure-configuration.htmProduct, Vendor Advisory
https://support.solarwinds.com/SuccessCenter/s/article/Mitigate-the-Stored-XSS-via-Help-Server-setting-CVE-2021-35240?language=en_USPatch, Vendor Advisory
https://support.solarwinds.com/SuccessCenter/s/article/Orion-Platform-2020-2-6-Hotfix-1?language=en_USMitigation, Vendor Advisory
https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35240Vendor Advisory

Timeline

Published: Aug 31, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-35240?

A security researcher stored XSS via a Help Server setting. This affects customers using Internet Explorer, because they do not support 'rel=noopener'.

How severe is CVE-2021-35240?

CVE-2021-35240 has a CVSS score of 4.8/10 (MEDIUM severity). The EPSS model estimates a 1.07% probability of exploitation in the next 30 days.

How do I fix CVE-2021-35240?

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-2021-35240?

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

Scan your code now

Source: NVD / NIST