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RUSTSEC-2025-0135 (CVE-2025-66622)

Vulnerability from osv_rustsec – Published: 2025-12-08 12:00 – Updated: 2025-12-08 12:23 – Source website
VLAI
Summary
matrix-sdk-base: Denial of service due to custom `m.room.join_rules` events
Details

The matrix-sdk-base crate is unable to handle responses that include custom m.room.join_rules values due to a serialization bug.

This can be exploited to cause a denial-of-service condition, if a user is invited to a room with non-standard join rules, the crate's sync process will stall, preventing further processing for all rooms.

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "categories": [
          "denial-of-service"
        ],
        "cvss": null,
        "informational": null
      },
      "ecosystem_specific": {
        "affected_functions": null,
        "affects": {
          "arch": [],
          "functions": [],
          "os": []
        }
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "matrix-sdk-base",
        "purl": "pkg:cargo/matrix-sdk-base"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.0.0-0"
            },
            {
              "fixed": "0.16.0"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "versions": []
    }
  ],
  "aliases": [
    "CVE-2025-66622",
    "GHSA-jj6p-3m75-g2p3"
  ],
  "database_specific": {
    "license": "CC0-1.0"
  },
  "details": "The matrix-sdk-base crate is unable to handle responses that include custom\nm.room.join_rules values due to a serialization bug.\n\nThis can be exploited to cause a denial-of-service condition, if a user is\ninvited to a room with non-standard join rules, the crate\u0027s sync process will\nstall, preventing further processing for all rooms.",
  "id": "RUSTSEC-2025-0135",
  "modified": "2025-12-08T12:23:54Z",
  "published": "2025-12-08T12:00:00Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://crates.io/crates/matrix-sdk-base"
    },
    {
      "type": "ADVISORY",
      "url": "https://rustsec.org/advisories/RUSTSEC-2025-0135.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-jj6p-3m75-g2p3"
    }
  ],
  "related": [],
  "severity": [],
  "summary": "matrix-sdk-base: Denial of service due to custom `m.room.join_rules` events"
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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