{
  "schema_version": "1.4.0",
  "id": "GHSA-v83q-83hj-rw38",
  "modified": "2025-02-28T17:46:36Z",
  "published": "2025-02-28T17:46:36Z",
  "aliases": [],
  "summary": "ntpd NTS client denial of service via wrongly sized cookies",
  "details": "Two denial of service vulnerabilities were found in ntpd-rs related to the handling of NTS cookies in our client functionality. Whenever an NTS source is configured and the server behind that source is sending zero-sized cookies or cookies larger than what would fit in our buffer size, ntpd-rs would crash. Only configured NTS sources can abuse these vulnerabilities. NTP sources or third parties that are not configured cannot make use of these vulnerabilities.\n\nFor zero-sized cookies: a division by zero would force an exit when the number of new cookies that would need to be requested is calculated. In ntpd-rs 1.5.0 a check was added to prevent the division by zero.\n\nFor large cookies: while trying to send a NTP request with the cookie included, the buffer is too small to handle the cookie and an exit of ntpd-rs is forced once a write to the buffer is attempted. The memory outside the buffer would not be written to in this case. In ntpd-rs 1.5.0 a check was added that prevents accepting cookies larger than 350 bytes.\n\nUsers of older versions of ntpd-rs are recommended to update to the latest version. If an update is impossible, it is recommended to only add NTS sources to ntpd-rs that are trusted to not abuse this bug.",
  "severity": [
    {
      "type": "CVSS_V4",
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "ntpd"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.5.0"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pendulum-project/ntpd-rs/security/advisories/GHSA-v83q-83hj-rw38"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pendulum-project/ntpd-rs/commit/10a103b471dae25ac598140df0c195b6531bf716"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pendulum-project/ntpd-rs/commit/37dd8d9a0faa03e7dfe3a4bf64953010f075c3e2"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pendulum-project/ntpd-rs"
    }
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-369",
      "CWE-703"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2025-02-28T17:46:36Z",
    "nvd_published_at": null
  }
}