CVE-2026-66730

facil.io 0.6.0 through 0.7.6 contains a denial-of-service vulnerability in the multipart body parser that allows an unauthenticated remote attacker to permanently freeze worker processes at 100% CPU by sending a multipart/form-data request with a partial closing boundary. The missing progress guard in the parser loop causes http_mime_parse to return 0 bytes consumed without setting done or error flags, causing the calling loop to re-invoke the parser on the same buffer indefinitely, exhausting all workers and permanently disabling the server until manually restarted.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/theopaid/Infinite-Loop-DoS-in-facil.io-MIME-Parser
https://tpaidakis.com/writeups/facilio-parser-dos/
https://www.vulncheck.com/advisories/facil-io-infinite-loop-dos-via-multipart-mime-body-parser

Configurations

No configuration.

History

24 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) facil.io 0.6.0 hasta 0.7.6 contiene una vulnerabilidad de denegación de servicio en el analizador de cuerpo multipart que permite a un atacante remoto no autenticado congelar permanentemente los procesos de trabajador al 100% de CPU enviando una solicitud multipart/form-data con un límite de cierre parcial. La guarda de progreso faltante en el bucle del analizador hace que http_mime_parse devuelva 0 bytes consumidos sin establecer las banderas done o error, haciendo que el bucle de llamada vuelva a invocar el analizador en el mismo búfer indefinidamente, agotando todos los trabajadores y deshabilitando permanentemente el servidor hasta que se reinicie manualmente.

Information

Published : 2026-07-27 17:16

Updated : 2026-10-24 13:10

NVD link : CVE-2026-66730

Mitre link : CVE-2026-66730

CVE.ORG link : CVE-2026-66730

JSON object : View

Products Affected

No product.

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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