{
  "modified": "2025-08-09T19:01:27Z",
  "published": "2009-02-20T19:30:00Z",
  "id": "CVE-2009-0654",
  "details": "Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and an exit router, to confirm that a sender and receiver are communicating via vectors involving (1) replaying, (2) modifying, (3) inserting, or (4) deleting a single cell, and then observing cell recognition errors at the exit router.  NOTE: the vendor disputes the significance of this issue, noting that the product's design \"accepted end-to-end correlation as an attack that is too expensive to solve.\"",
  "references": [
    {
      "type": "ARTICLE",
      "url": "http://blog.torproject.org/blog/one-cell-enough"
    },
    {
      "type": "EVIDENCE",
      "url": "http://www.blackhat.com/presentations/bh-dc-09/Fu/BlackHat-DC-09-Fu-Break-Tors-Anonymity.pdf"
    },
    {
      "type": "WEB",
      "url": "http://www.blackhat.com/html/bh-dc-09/bh-dc-09-archives.html#Fu"
    }
  ]
}