CVE-2021-33818
Estado: ModificadaAlta (7.5)—
An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67. Attackers can use slowhttptest tool to send incomplete HTTP request, which could make server keep waiting for the packet to finish the connection, until its resource exhausted. Then the web server is denial-of-service.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.93%
- Percentil entre todas las CVEs puntuadas: 79
- 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-400
Referencias
- https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33818.md
- https://github.com/shekyan/slowhttptest
- https://store.ui.com/collections/unifi-protect-cameras/products/unifi-video-g3-flex-camera
- https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33818.md
- https://github.com/shekyan/slowhttptest
- https://store.ui.com/collections/unifi-protect-cameras/products/unifi-video-g3-flex-camera
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-33818",
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"authentication": "NONE",
"integrityImpact": "NONE",
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"availabilityImpact": "PARTIAL",
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"published": "2021-06-18T19:15:07.497",
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"lang": "en",
"value": "An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67. Attackers can use slowhttptest tool to send incomplete HTTP request, which could make server keep waiting for the packet to finish the connection, until its resource exhausted. Then the web server is denial-of-service."
},
{
"lang": "es",
"value": "Se ha detectado un problema en UniFi Protect G3 FLEX Camera versión UVC.v4.30.0.67. Unos atacantes pueden usar la herramienta slowhttptest para enviar peticiones HTTP incompletas, lo que podría hacer que el servidor siga esperando a que el paquete termine la conexión, hasta que sean agotados sus recursos. Entonces el servidor web sufre una denegación de servicio"
}
],
"lastModified": "2026-06-17T03:55:16.120",
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