{
  "number": 5393,
  "title": "Addressing an Amplification Vulnerability in Session Initiation Protocol (SIP) Forking Proxies",
  "authors": [
    "R. Sparks, Ed.",
    "S. Lawrence",
    "A. Hawrylyshen",
    "B. Campen"
  ],
  "published": "2008-12",
  "status": "Proposed Standard",
  "stream": "IETF",
  "area": "rai",
  "working_group": "sip",
  "pages": 20,
  "formats": [
    "TXT",
    "HTML"
  ],
  "abstract": "This document normatively updates RFC 3261, the Session Initiation Protocol (SIP), to address a security vulnerability identified in SIP proxy behavior. This vulnerability enables an attack against SIP networks where a small number of legitimate, even authorized, SIP requests can stimulate massive amounts of proxy-to-proxy traffic.\n\nThis document strengthens loop-detection requirements on SIP proxies when they fork requests (that is, forward a request to more than one destination). It also corrects and clarifies the description of the loop-detection algorithm such proxies are required to implement. Additionally, this document defines a Max-Breadth mechanism for limiting the number of concurrent branches pursued for any given request. [STANDARDS-TRACK]",
  "keywords": [
    "SIP",
    "application-layer",
    "application",
    "layer",
    "multimedia",
    "multicast",
    "unicast"
  ],
  "draft": "draft-ietf-sip-fork-loop-fix-08",
  "doi": "10.17487/RFC5393",
  "updates": [
    "RFC3261"
  ],
  "urls": {
    "html": "https://rfc.dk/rfc5393/",
    "text": "https://rfc.dk/rfc5393.txt",
    "rfc_editor": "https://www.rfc-editor.org/rfc/rfc5393",
    "datatracker": "https://datatracker.ietf.org/doc/rfc5393/"
  },
  "text_modified": "2008-12-10T18:39:22Z"
}