CVE-2021-47870 (GCVE-0-2021-47870)
Vulnerability from cvelistv5 – Published: 2026-01-21 17:32 – Updated: 2026-05-12 20:45
VLAI
EPSS
VEX
Title
GetSimple CMS My SMTP Contact Plugin 1.1.2 - Stored XSS
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-22 16:45 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Stored Cross-site Scripting')
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/boku7/gsSMTP-Csrf2Xss2RCE/ | technical-descriptionexploit |
| http://get-simple.info | product |
| https://github.com/GetSimpleCMS/GetSimpleCMS | product |
| https://www.exploit-db.com/exploits/49798 | exploit |
| https://www.vulncheck.com/advisories/getsimple-cm… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| GetSimple CMS | My SMTP Contact Plugin |
Affected:
1.1.2
cpe:2.3:a:getsimple-ce:getsimple_cms:1.1.2:*:*:*:*:*:*:* |
Date Public
2021-04-23 00:00
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Sightings
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.