CVE-2021-3030

MEDIUM
Published Sep 17, 2026 Modified Sep 22, 2026 CWE-79

Description

Cute Editor for ASP.NET 6.4 is vulnerable to reflected cross-site scripting caused by improper validation of the Theme GET parameter in colorpicker_more.aspx. A remote, unauthenticated attacker can craft a URL that, once opened by a victim in a browser session authenticated to a site running the vulnerable component, executes arbitrary JavaScript in the security context of that site.

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CVSS v3.1 Score

6.1
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0027
Probability of exploitation
0.17%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

References

Frequently Asked Questions

What is CVE-2021-3030? +
Cute Editor for ASP.NET 6.4 is vulnerable to reflected cross-site scripting caused by improper validation of the Theme GET parameter in colorpicker_more.aspx. A remote, unauthenticated attacker can craft a URL that, once opened by a victim in a browser session authenticated to a site running the vulnerable component, executes arbitrary JavaScript in the security context of that site. It has a CVSS v3.1 base score of 6.1 (MEDIUM).
How severe is CVE-2021-3030? +
CVE-2021-3030 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0027, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2021-3030? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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