CVE-2021-47931

Description

Exponent CMS 2.6 contains a stored cross-site scripting vulnerability that allows authenticated attackers to inject malicious scripts through the Title and Text Block parameters in the text editing endpoint. Attackers can inject iframe payloads with embedded SVG onload events to execute arbitrary JavaScript, and the application also exposes database credentials in responses and lacks brute-force protection on authentication endpoints.

CVSS v3.1 Score

6.4

MEDIUM

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

EPSS — Exploit Prediction

0.0005

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

Other References

https://www.exploit-db.com/exploits/50611 https://www.exponentcms.org/ https://www.vulncheck.com/advisories/exponent-cms-multiple-vulnerabilities-stored-xss-authentication

Frequently Asked Questions

What is CVE-2021-47931? +

Exponent CMS 2.6 contains a stored cross-site scripting vulnerability that allows authenticated attackers to inject malicious scripts through the Title and Text Block parameters in the text editing endpoint. Attackers can inject iframe payloads with embedded SVG onload events to execute arbitrary JavaScript, and the application also exposes database credentials in responses and lacks brute-force protection on authentication endpoints. It has a CVSS v3.1 base score of 6.4 (MEDIUM).

How severe is CVE-2021-47931? +

CVE-2021-47931 has a CVSS v3.1 score of 6.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0005, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2021-47931? +

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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