Search criteria
ⓘ
Use full-text search for keyword queries.
Combine vendor, product, and sources to narrow results.
Enable “Apply ordering” to sort by dates instead of relevance.
Related vulnerabilities
GHSA-52JH-2XXH-PWH6
Vulnerability from github – Published: 2026-03-24 21:29 – Updated: 2026-03-24 21:29
VLAI?
Summary
NATS Server panic via malicious compression on leafnode port
Details
Background
NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.
When configured to accept leafnode connections (for a hub/spoke topology of multiple nats-servers), then the default configuration allows for negotiating compression; a malicious remote NATS server can trigger a server panic via that compression.
Problem Description
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).
Context: a NATS server can form various clustering topologies, including local clusters, and superclusters of clusters, but leafnodes allow for separate administrative domains to link together with limited data communication; eg, a server in a moving vehicle might use a local leafnode for agents to connect to, and sync up to a central service as and when available. The leafnode configuration here is where the central server allows other NATS servers to connect into it, almost like regular NATS clients. Documentation examples typically use port 7422 for leafnode communications.
Affected Versions
Version 2, prior to v2.11.14 or v2.12.5
Workarounds
Disable compression on the leafnode port:
leafnodes {
port: 7422
compression: off
}
Severity ?
7.5 (High)
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/nats-io/nats-server/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.11.14"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/nats-io/nats-server/v2"
},
"ranges": [
{
"events": [
{
"introduced": "2.12.0-RC.1"
},
{
"fixed": "2.12.5"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-29785"
],
"database_specific": {
"cwe_ids": [
"CWE-476"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-24T21:29:06Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "### Background\n\nNATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.\n\nWhen configured to accept leafnode connections (for a hub/spoke topology of multiple nats-servers), then the default configuration allows for negotiating compression; a malicious remote NATS server can trigger a server panic via that compression.\n\n### Problem Description\n\nIf 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).\n\nContext: a NATS server can form various clustering topologies, including local clusters, and superclusters of clusters, but leafnodes allow for separate administrative domains to link together with limited data communication; eg, a server in a moving vehicle might use a local leafnode for agents to connect to, and sync up to a central service as and when available. The leafnode configuration here is where the central server allows other NATS servers to connect into it, almost like regular NATS clients. Documentation examples typically use port 7422 for leafnode communications.\n\n### Affected Versions\n\nVersion 2, prior to v2.11.14 or v2.12.5\n\n### Workarounds\n\nDisable compression on the leafnode port:\n\n```\nleafnodes {\n port: 7422\n compression: off\n}\n```",
"id": "GHSA-52jh-2xxh-pwh6",
"modified": "2026-03-24T21:29:06Z",
"published": "2026-03-24T21:29:06Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-52jh-2xxh-pwh6"
},
{
"type": "WEB",
"url": "https://github.com/nats-io/nats-server/commit/a1488de6f2ba6e666aef0f9cce0016f7f167d6a8"
},
{
"type": "WEB",
"url": "https://advisories.nats.io/CVE/secnote-2026-04.txt"
},
{
"type": "PACKAGE",
"url": "https://github.com/nats-io/nats-server"
}
],
"schema_version": "1.4.0",
"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"
}
WID-SEC-W-2026-0641
Vulnerability from csaf_certbund - Published: 2026-03-09 23:00 - Updated: 2026-03-09 23:00Summary
NATS Server: Mehrere Schwachstellen ermöglichen Denial of Service
Severity
Mittel
Notes
Das BSI ist als Anbieter für die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch dafür verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgfältig im Einzelfall zu prüfen.
Produktbeschreibung: Der NATS-Server ist ein Server für NATS.io, das Cloud- und Edge-native Messaging-System.
Angriff: Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in NATS Server ausnutzen, um einen Denial of Service Angriff durchzuführen.
Betroffene Betriebssysteme: - Sonstiges
- UNIX
References
{
"document": {
"aggregate_severity": {
"text": "mittel"
},
"category": "csaf_base",
"csaf_version": "2.0",
"distribution": {
"tlp": {
"label": "WHITE",
"url": "https://www.first.org/tlp/"
}
},
"lang": "de-DE",
"notes": [
{
"category": "legal_disclaimer",
"text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
},
{
"category": "description",
"text": "Der NATS-Server ist ein Server f\u00fcr NATS.io, das Cloud- und Edge-native Messaging-System.",
"title": "Produktbeschreibung"
},
{
"category": "summary",
"text": "Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in NATS Server ausnutzen, um einen Denial of Service Angriff durchzuf\u00fchren.",
"title": "Angriff"
},
{
"category": "general",
"text": "- Sonstiges\n- UNIX",
"title": "Betroffene Betriebssysteme"
}
],
"publisher": {
"category": "other",
"contact_details": "csaf-provider@cert-bund.de",
"name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
"namespace": "https://www.bsi.bund.de"
},
"references": [
{
"category": "self",
"summary": "WID-SEC-W-2026-0641 - CSAF Version",
"url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-0641.json"
},
{
"category": "self",
"summary": "WID-SEC-2026-0641 - Portal Version",
"url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-0641"
},
{
"category": "external",
"summary": "NATS Advisory vom 2026-03-09",
"url": "https://advisories.nats.io/CVE/secnote-2026-03.txt"
},
{
"category": "external",
"summary": "NATS Advisory vom 2026-03-09",
"url": "https://advisories.nats.io/CVE/secnote-2026-04.txt"
}
],
"source_lang": "en-US",
"title": "NATS Server: Mehrere Schwachstellen erm\u00f6glichen Denial of Service",
"tracking": {
"current_release_date": "2026-03-09T23:00:00.000+00:00",
"generator": {
"date": "2026-03-10T10:06:32.343+00:00",
"engine": {
"name": "BSI-WID",
"version": "1.5.0"
}
},
"id": "WID-SEC-W-2026-0641",
"initial_release_date": "2026-03-09T23:00:00.000+00:00",
"revision_history": [
{
"date": "2026-03-09T23:00:00.000+00:00",
"number": "1",
"summary": "Initiale Fassung"
}
],
"status": "final",
"version": "1"
}
},
"product_tree": {
"branches": [
{
"branches": [
{
"branches": [
{
"category": "product_version_range",
"name": "\u003cv2.11.14",
"product": {
"name": "Open Source NATS Server \u003cv2.11.14",
"product_id": "T051494"
}
},
{
"category": "product_version",
"name": "v2.11.14",
"product": {
"name": "Open Source NATS Server v2.11.14",
"product_id": "T051494-fixed",
"product_identification_helper": {
"cpe": "cpe:/a:nats:nats_server:v2.11.14"
}
}
},
{
"category": "product_version_range",
"name": "\u003cv2.12.5",
"product": {
"name": "Open Source NATS Server \u003cv2.12.5",
"product_id": "T051495"
}
},
{
"category": "product_version",
"name": "v2.12.5",
"product": {
"name": "Open Source NATS Server v2.12.5",
"product_id": "T051495-fixed",
"product_identification_helper": {
"cpe": "cpe:/a:nats:nats_server:v2.12.5"
}
}
}
],
"category": "product_name",
"name": "NATS Server"
}
],
"category": "vendor",
"name": "Open Source"
}
]
},
"vulnerabilities": [
{
"cve": "CVE-2026-27889",
"product_status": {
"known_affected": [
"T051494",
"T051495"
]
},
"release_date": "2026-03-09T23:00:00.000+00:00",
"title": "CVE-2026-27889"
},
{
"cve": "CVE-2026-29785",
"product_status": {
"known_affected": [
"T051494",
"T051495"
]
},
"release_date": "2026-03-09T23:00:00.000+00:00",
"title": "CVE-2026-29785"
}
]
}