nvd-json-data-feeds/CVE-2021/CVE-2021-212xx/CVE-2021-21294.json

{
  "id": "CVE-2021-21294",
  "sourceIdentifier": "security-advisories@github.com",
  "published": "2021-02-02T22:15:12.387",
  "lastModified": "2022-10-24T20:48:46.103",
  "vulnStatus": "Analyzed",
  "descriptions": [
    {
      "lang": "en",
      "value": "Http4s (http4s-blaze-server) is a minimal, idiomatic Scala interface for HTTP services. Http4s before versions 0.21.17, 0.22.0-M2, and 1.0.0-M14 have a vulnerability which can lead to a denial-of-service. Blaze-core, a library underlying http4s-blaze-server, accepts connections unboundedly on its selector pool. This has the net effect of amplifying degradation in services that are unable to handle their current request load, since incoming connections are still accepted and added to an unbounded queue. Each connection allocates a socket handle, which drains a scarce OS resource. This can also confound higher level circuit breakers which work based on detecting failed connections. http4s provides a general \"MaxActiveRequests\" middleware mechanism for limiting open connections, but it is enforced inside the Blaze accept loop, after the connection is accepted and the socket opened. Thus, the limit only prevents the number of connections which can be simultaneously processed, not the number of connections which can be held open. In 0.21.17, 0.22.0-M2, and 1.0.0-M14, a new \"maxConnections\" property, with a default value of 1024, has been added to the `BlazeServerBuilder`. Setting the value to a negative number restores unbounded behavior, but is strongly disrecommended. The NIO2 backend does not respect `maxConnections`. Its use is now deprecated in http4s-0.21, and the option is removed altogether starting in http4s-0.22. There are several possible workarounds described in the refrenced GitHub Advisory GHSA-xhv5-w9c5-2r2w."
    },
    {
      "lang": "es",
      "value": "Http4s (http4s-blaze-server) es una interfaz Scala m\u00ednima e idiom\u00e1tica para servicios HTTP. Http4s anterior a versiones 0.21.17, 0.22.0-M2 y 1.0.0-M14, presentan una vulnerabilidad que puede conllevar a una denegaci\u00f3n de servicio. Blaze-core, una biblioteca subyacente a http4s-blaze-server, acepta conexiones ilimitadas en su grupo de selectores. Esto tiene el efecto neto de amplificar la degradaci\u00f3n en los servicios que no pueden manejar su carga de peticiones actual, ya que las conexiones entrantes a\u00fan se aceptan y agregan a una cola ilimitada. Cada conexi\u00f3n asigna un identificador de socket, lo que agota un recurso escaso del sistema operativo. Esto tambi\u00e9n puede confundir a los disyuntores de nivel superior que funcionan bas\u00e1ndose en la detecci\u00f3n de conexiones en fallo. http4s proporciona un mecanismo de middleware \"MaxActiveRequests\" general para limitar las conexiones abiertas, pero se aplica dentro del bucle de aceptaci\u00f3n de Blaze, despu\u00e9s de que se acepta la conexi\u00f3n y se abre el socket. Por lo tanto, el l\u00edmite solo impide el n\u00famero de conexiones que se pueden procesar simult\u00e1neamente, no el n\u00famero de conexiones que se pueden mantener abiertas. En 0.21.17, 0.22.0-M2 y 1.0.0-M14, se agreg\u00f3 una nueva propiedad \"maxConnections\", con un valor predeterminado de 1024, al \"BlazeServerBuilder\". Establecer el valor en un n\u00famero negativo restaura el comportamiento ilimitado, pero se desaconseja en\u00e9rgicamente. El backend de NIO2 no respeta \"maxConnections\". Su uso ahora es obsoleto en http4s-0.21, y la opci\u00f3n se elimina por completo a partir de http4s-0.22. Existen varias posibles soluciones que se describen en el Aviso de GitHub referenciado GHSA-xhv5-w9c5-2r2w"
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