CVE-2021-42662
A Stored Cross Site Scripting (XSS) vulnerability exists in Sourcecodester Online Event Booking and Reservation System in PHP/MySQL via the Holiday reason parameter. An attacker can leverage this vulnerability in order to run javascript commands on the web server surfers behalf, which can lead to cookie stealing and more.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- Puntuación base: 5.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.67%
- Percentil entre todas las CVEs puntuadas: 76
- Fecha de la puntuación: 7/10/2026
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).
💥 Exploits públicos
Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.
- Prueba de concepto en GitHub (no verificada) · Lista de pruebas de concepto en GitHub
⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.
Tecnologías afectadas (1)
CWE
- CWE-79
Referencias
- http://packetstormsecurity.com/files/164615/Online-Event-Booking-And-Reservation-System-1.0-Cross-Site-Scripting.html
- https://github.com/TheHackingRabbi/CVE-2021-42662
- https://www.exploit-db.com/exploits/50450
- https://www.sourcecodester.com/php/14241/online-event-booking-and-reservation-system-phpmysql.html
- http://packetstormsecurity.com/files/164615/Online-Event-Booking-And-Reservation-System-1.0-Cross-Site-Scripting.html
- https://github.com/TheHackingRabbi/CVE-2021-42662
- https://www.exploit-db.com/exploits/50450
- https://www.sourcecodester.com/php/14241/online-event-booking-and-reservation-system-phpmysql.html
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-42662",
"cveTags": [],
"metrics": {
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"baseScore": 3.5,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:S/C:N/I:P/A:N",
"authentication": "SINGLE",
"integrityImpact": "PARTIAL",
"accessComplexity": "MEDIUM",
"availabilityImpact": "NONE",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "LOW",
"obtainAllPrivilege": false,
"exploitabilityScore": 6.8,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": true
}
],
"cvssMetricV31": [
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "LOW",
"confidentialityImpact": "LOW"
},
"impactScore": 2.7,
"exploitabilityScore": 2.3
}
]
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"affected": [
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"affectedData": [
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"versions": [
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],
"published": "2021-11-05T11:15:08.007",
"references": [
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{
"url": "https://www.sourcecodester.com/php/14241/online-event-booking-and-reservation-system-phpmysql.html",
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{
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{
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"weaknesses": [
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"source": "nvd@nist.gov",
"description": [
{
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"descriptions": [
{
"lang": "en",
"value": "A Stored Cross Site Scripting (XSS) vulnerability exists in Sourcecodester Online Event Booking and Reservation System in PHP/MySQL via the Holiday reason parameter. An attacker can leverage this vulnerability in order to run javascript commands on the web server surfers behalf, which can lead to cookie stealing and more."
},
{
"lang": "es",
"value": "Se presenta una vulnerabilidad de tipo Cross Site Scripting (XSS) almacenada en Sourcecodester Online Event Booking and Reservation System in PHP/MySQL por medio del parámetro Holiday reason. Un atacante puede aprovechar esta vulnerabilidad para ejecutar comandos javascript en nombre de los navegantes del servidor web, que puede conllevar al robo de cookies y más"
}
],
"lastModified": "2026-06-17T04:09:55.727",
"configurations": [
{
"nodes": [
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"cpeMatch": [
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"criteria": "cpe:2.3:a:online_event_booking_and_reservation_system_project:online_event_booking_and_reservation_system:2.3.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E052D7DA-B44E-48D6-B44B-8BB974D47DFF"
}
],
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}