CVE-2021-38143
Estado: ModificadaMedia (6.1)—
An issue was discovered in Form Tools through 3.0.20. When an administrator creates a customer account, it is possible for the customer to log in and proceed with a change of name and last name. However, these fields are vulnerable to XSS payload insertion, being triggered in the admin panel when the admin tries to see the client list. This type of XSS (stored) can lead to the extraction of the PHPSESSID cookie belonging to the admin.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- Puntuación base: 6.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.35%
- Percentil entre todas las CVEs puntuadas: 71
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-79
Referencias
- https://bernardofsr.github.io/blog/2021/form-tools/
- https://github.com/bernardofsr/CVEs-With-PoC/blob/main/PoCs/Form%20Tools/README.md
- https://github.com/formtools/core
- https://www.formtools.org/
- https://bernardofsr.github.io/blog/2021/form-tools/
- https://github.com/bernardofsr/CVEs-With-PoC/blob/main/PoCs/Form%20Tools/README.md
- https://github.com/formtools/core
- https://www.formtools.org/
JSON original (NVD)
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{
"id": "CVE-2021-38143",
"cveTags": [],
"metrics": {
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"type": "Primary",
"source": "nvd@nist.gov",
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"baseScore": 4.3,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "MEDIUM",
"availabilityImpact": "NONE",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "LOW"
},
"impactScore": 2.7,
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"affected": [
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"affectedData": [
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"versions": [
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],
"published": "2021-08-31T05:15:06.563",
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"tags": [
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"vulnStatus": "Modified",
"weaknesses": [
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"type": "Primary",
"source": "nvd@nist.gov",
"description": [
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"lang": "en",
"value": "CWE-79"
}
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}
],
"descriptions": [
{
"lang": "en",
"value": "An issue was discovered in Form Tools through 3.0.20. When an administrator creates a customer account, it is possible for the customer to log in and proceed with a change of name and last name. However, these fields are vulnerable to XSS payload insertion, being triggered in the admin panel when the admin tries to see the client list. This type of XSS (stored) can lead to the extraction of the PHPSESSID cookie belonging to the admin."
},
{
"lang": "es",
"value": "Se ha detectado un problema en Form Tools versiones hasta 3.0.20. Cuando un administrador crea una cuenta de cliente, es posible que el cliente inicie sesión y proceda a un cambio de nombre y apellido. Sin embargo, estos campos son vulnerables a una inserción de cargas útiles de tipo XSS, siendo desencadenadas en el panel de administración cuando el administrador intenta ver la lista de clientes. Este tipo de ataque XSS (almacenado) puede conllevar a una extracción de la cookie PHPSESSID perteneciente al admin"
}
],
"lastModified": "2026-06-17T04:01:33.710",
"configurations": [
{
"nodes": [
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"cpeMatch": [
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"matchCriteriaId": "F3C206DF-25E1-483F-856F-BCACE79F6736",
"versionEndIncluding": "3.0.20"
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"sourceIdentifier": "cve@mitre.org"
}