CVE-2021-47870

low-risk
Published 2026-01-21

GetSimple CMS My SMTP Contact Plugin 1.1.2 suffers from a Stored Cross-Site Scripting (XSS) vulnerability. The plugin attempts to sanitize user input using htmlspecialchars(), but this can be bypassed by passing dangerous characters as escaped hex bytes. This allows attackers to inject arbitrary client-side code that executes in the administrator's browser when visiting a malicious page.

Do I need to act?

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0.09% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.4/10 Medium
NETWORK / LOW complexity

Affected Products (1)

Affected Vendors

Get-Simple

References (5)

Product http://get-simple.info
Product https://github.com/GetSimpleCMS/GetSimpleCMS
Exploit https://github.com/boku7/gsSMTP-Csrf2Xss2RCE/
Exploit https://www.exploit-db.com/exploits/49798
Third Party Advisory https://www.vulncheck.com/advisories/getsimple-cms-my-smtp-contact-plugin-stored...
26
/ 100
low-risk
Severity 21/34 · High
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal