{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.11.14"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "797d2514fdb29ccb2b654f7fefbcb166ccb66cf1"
            }
          ],
          "repo": "https://github.com/nats-io/nats-server",
          "type": "GIT"
        },
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "2.12.0-RC.1"
              },
              {
                "fixed": "2.12.5"
              }
            ]
          },
          "events": [
            {
              "introduced": "4dccf778573cd9a9e52fb8f119718459f6f2f761"
            },
            {
              "fixed": "0f6c831ec1df25bc3dc81d25faae0ed0bac15a96"
            }
          ],
          "repo": "https://github.com/nats-io/nats-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-52jh-2xxh-pwh6"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-476"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29785.json"
  },
  "details": "NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.14 and 2.12.5, if the nats-server has the \"leafnode\" configuration enabled (not default), then anyone who can connect can crash the nats-server by triggering a panic. This happens pre-authentication and requires that compression be enabled (which it is, by default, when leafnodes are used). Versions 2.11.14 and 2.12.5 contain a fix. As a workaround, disable compression on the leafnode port.",
  "id": "CVE-2026-29785",
  "modified": "2026-04-01T23:09:00.691307617Z",
  "published": "2026-03-25T19:38:44.587Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://advisories.nats.io/CVE/secnote-2026-04.txt"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29785.json"
    },
    {
      "type": "FIX",
      "url": "https://github.com/nats-io/nats-server/commit/a1488de6f2ba6e666aef0f9cce0016f7f167d6a8"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-52jh-2xxh-pwh6"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-29785"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "NATS Server panic via malicious compression on leafnode port"
}