{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:matrix:matrix-appservice-bridge:*:*:*:*:*:node.js:*:*",
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.6.1"
              }
            ],
            "source": [
              "CPE_RANGE",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7e32516a211b9d13433fc5a6016642e3ad2fc974"
            },
            {
              "fixed": "b69e745584a34fcfd858df33e4631e420da07b9f"
            }
          ],
          "repo": "https://github.com/matrix-org/matrix-appservice-bridge",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-35g4-qx3c-vjhx"
  ],
  "database_specific": {},
  "details": "Matrix-appservice-bridge is the bridging service for the Matrix communication program's application services. In versions 2.6.0 and earlier, if a bridge has room upgrade handling turned on in the configuration (the `roomUpgradeOpts` key when instantiating a new `Bridge` instance.), any `m.room.tombstone` event it encounters will be used to unbridge the current room and bridge into the target room. However, the target room `m.room.create` event is not checked to verify if the `predecessor` field contains the previous room. This means that any malicious admin of a bridged room can repoint the traffic to a different room without the new room being aware. Versions 2.6.1 and greater are patched. As a workaround, disabling the automatic room upgrade handling can be done by removing the `roomUpgradeOpts` key from the `Bridge` class options.",
  "id": "CVE-2021-32659",
  "modified": "2026-07-08T05:37:30.574529045Z",
  "published": "2021-06-16T19:15:38.830Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/matrix-org/matrix-appservice-bridge/security/advisories/GHSA-35g4-qx3c-vjhx"
    },
    {
      "type": "FIX",
      "url": "https://github.com/matrix-org/matrix-appservice-bridge/commit/b69e745584a34fcfd858df33e4631e420da07b9f"
    },
    {
      "type": "FIX",
      "url": "https://github.com/matrix-org/matrix-appservice-bridge/releases/tag/2.6.1"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}