CVE-2026-29785 (GCVE-0-2026-29785)

Vulnerability from cvelistv5 – Published: 2026-03-25 19:38 – Updated: 2026-03-25 19:40
VLAI?
Title
NATS Server panic via malicious compression on leafnode port
Summary
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.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
Vendor Product Version
nats-io nats-server Affected: < 2.11.14
Affected: >= 2.12.0-RC.1, < 2.12.5
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          "vendor": "nats-io",
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            {
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        }
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            "privilegesRequired": "NONE",
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            "userInteraction": "NONE",
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            "version": "3.1"
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      "problemTypes": [
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          "descriptions": [
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              "cweId": "CWE-476",
              "description": "CWE-476: NULL Pointer Dereference",
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      "providerMetadata": {
        "dateUpdated": "2026-03-25T19:40:51.282Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
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      "source": {
        "advisory": "GHSA-52jh-2xxh-pwh6",
        "discovery": "UNKNOWN"
      },
      "title": "NATS Server panic via malicious compression on leafnode port"
    }
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  "cveMetadata": {
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    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-29785",
    "datePublished": "2026-03-25T19:38:44.587Z",
    "dateReserved": "2026-03-04T16:26:02.899Z",
    "dateUpdated": "2026-03-25T19:40:51.282Z",
    "state": "PUBLISHED"
  },
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  }
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