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.
Security readout for executives and security teams
CVE-2021-47870 is a stored cross-site scripting issue in GetSimple CMS My SMTP Contact Plugin 1.1.2. A lower-privileged attacker can save malicious content that later runs in an administrator’s browser. This could expose admin actions or session context, but sources do not show confirmed active exploitation. Exposure is limited to sites running GetSimple CMS with My SMTP Contact Plugin version 1.1.2 installed and reachable by users able to submit plugin-handled content. Treat as a targeted website-administration risk, not an enterprise-wide emergency. Prioritize externally reachable GetSimple CMS instances and sites where untrusted users can submit content. Remove or disable the plugin if no vendor-supported fix is available. Mitigation focus: Inventory GetSimple CMS sites for My SMTP Contact Plugin 1.1.2.; Check vendor or project guidance for an official fix or replacement.; Disable or remove the plugin if it is not required..
Prepared
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Potential ATT&CK relevance
Conservative CVE-to-ATT&CK context
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ATT&CK lookup starting points
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cwe · medium confidence lookup
CWE-79: User-session and phishing behavior lookup
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CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
CWE-79 · source CWE mapping
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.