Common Weakness Enumeration

CWE-942

Allowed

Permissive Cross-domain Security Policy with Untrusted Domains

Abstraction: Variant · Status: Incomplete

The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.

184 vulnerabilities reference this CWE, most recent first.

GHSA-FQ2G-WF56-3PRG

Vulnerability from github – Published: 2026-06-30 21:31 – Updated: 2026-06-30 21:31
VLAI
Details

IBM UCD - IBM DevOps Deploy 8.1 through 8.1.2.6, and 8.2 through 8.2.1.0 uses Cross-Origin Resource Sharing (CORS) which could allow an attacker to carry out privileged actions and retrieve sensitive information as the domain name is not being limited to only trusted domains.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-12084"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-30T20:17:28Z",
    "severity": "MODERATE"
  },
  "details": "IBM UCD - IBM DevOps Deploy 8.1 through 8.1.2.6, and 8.2 through 8.2.1.0 uses Cross-Origin Resource Sharing (CORS) which could allow an attacker to carry out privileged actions and retrieve sensitive information as the domain name is not being limited to only trusted domains.",
  "id": "GHSA-fq2g-wf56-3prg",
  "modified": "2026-06-30T21:31:44Z",
  "published": "2026-06-30T21:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-12084"
    },
    {
      "type": "WEB",
      "url": "https://www.ibm.com/support/pages/node/7277575"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-FQRJ-M2F5-X9PJ

Vulnerability from github – Published: 2026-06-12 18:31 – Updated: 2026-06-12 18:31
VLAI
Details

The Aqara Developer Portal (developer.aqara.com) and shared test environments (developer-test.aqara.com, aiot-test.aqara.com) exhibit cross-origin request sharing, which is an instance of "CWE-942: Permissive Cross-domain Policy with Untrusted Domains," and has an estimated CVSS of CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N (8.2 High).

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-50088"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-12T16:16:32Z",
    "severity": "HIGH"
  },
  "details": "The Aqara Developer Portal (developer.aqara.com) and shared test environments (developer-test.aqara.com, aiot-test.aqara.com) exhibit cross-origin request sharing, which is an instance of \"CWE-942: Permissive Cross-domain Policy with Untrusted Domains,\" and has an estimated CVSS of CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N (8.2 High).",
  "id": "GHSA-fqrj-m2f5-x9pj",
  "modified": "2026-06-12T18:31:59Z",
  "published": "2026-06-12T18:31:58Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50088"
    },
    {
      "type": "WEB",
      "url": "https://github.com/xn0tsa/theres-no-place-like-home"
    },
    {
      "type": "WEB",
      "url": "https://www.runzero.com/advisories/aqara-dev-portal-cors-cve-2026-50088"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-FWMW-87X4-WJV5

Vulnerability from github – Published: 2026-07-02 15:32 – Updated: 2026-07-02 15:32
VLAI
Details

A malicious actor who lures an authenticated user to a malicious page could exploit a Cross-Origin Resource Sharing (CORS) misconfiguration found in UniFi OS to trigger actions in UniFi OS using that user's session.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-55110"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-02T15:17:04Z",
    "severity": "HIGH"
  },
  "details": "A malicious actor who lures an authenticated user to a malicious page could exploit a Cross-Origin Resource Sharing (CORS) misconfiguration found in UniFi OS to trigger actions in UniFi OS using that user\u0027s session.",
  "id": "GHSA-fwmw-87x4-wjv5",
  "modified": "2026-07-02T15:32:13Z",
  "published": "2026-07-02T15:32:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55110"
    },
    {
      "type": "WEB",
      "url": "https://community.ui.com/releases/Security-Advisory-Bulletin-066-066/984eceb3-49c8-4227-942d-671c289b3afc"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G27J-74FP-XFPR

Vulnerability from github – Published: 2022-04-05 18:31 – Updated: 2025-04-14 22:07
VLAI
Summary
Insecure default value for CORS configuration
Details

Impact

The default value for the CORS_ENABLED and CORS_ORIGIN configuration was set to be very permissive by default. This could lead to unauthorized access in uncontrolled environments when the configuration hasn't been changed.

Patches

The default values for CORS have been changed in https://github.com/directus/directus/pull/12022 which is released under 9.7.0

Workarounds

Configure the CORS environment variables to match your project's usage, rather than leaving them at the (permissive) defaults.

For more information

If you have any questions or comments about this advisory: * Open an issue in directus/directus * Email us at security@directus.io

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "directus"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "9.7.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-26969"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-04-05T18:31:22Z",
    "nvd_published_at": "2022-12-26T06:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "### Impact\n\nThe default value for the `CORS_ENABLED` and `CORS_ORIGIN` configuration was set to be very permissive by default. This could lead to unauthorized access in uncontrolled environments when the configuration hasn\u0027t been changed.\n\n### Patches\n\nThe default values for CORS have been changed in https://github.com/directus/directus/pull/12022 which is released under 9.7.0\n\n### Workarounds\n\nConfigure the CORS environment variables to match your project\u0027s usage, rather than leaving them at the (permissive) defaults.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an issue in [directus/directus](https://github.com/directus/directus)\n* Email us at [security@directus.io](mailto:security@directus.io)",
  "id": "GHSA-g27j-74fp-xfpr",
  "modified": "2025-04-14T22:07:39Z",
  "published": "2022-04-05T18:31:22Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/directus/directus/security/advisories/GHSA-g27j-74fp-xfpr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-26969"
    },
    {
      "type": "WEB",
      "url": "https://github.com/directus/directus/pull/12022"
    },
    {
      "type": "WEB",
      "url": "https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/directus/directus"
    },
    {
      "type": "WEB",
      "url": "https://github.com/directus/directus/blob/8daed9c41baeaf1d08c1e292bf9f0dcef65e48fb/docs/configuration/config-options.md"
    },
    {
      "type": "WEB",
      "url": "https://github.com/directus/directus/releases/tag/v9.7.0"
    },
    {
      "type": "WEB",
      "url": "https://security.snyk.io/vuln/SNYK-JS-DIRECTUS-2441822"
    }
  ],
  "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:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Insecure default value for CORS configuration"
}

GHSA-G6H8-P8P4-98F2

Vulnerability from github – Published: 2026-07-17 15:32 – Updated: 2026-07-17 15:32
VLAI
Details

HCL Aftermarket EPC is vulnerable to attack as the application implements an HTML5 cross-origin resource sharing (CORS) policy for this request that allows access from any domain (*-Wildcard).

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-23578"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-17T14:17:18Z",
    "severity": "MODERATE"
  },
  "details": "HCL Aftermarket EPC is vulnerable to attack as the application implements an HTML5 cross-origin resource sharing (CORS) policy for this request that allows access from any domain (*-Wildcard).",
  "id": "GHSA-g6h8-p8p4-98f2",
  "modified": "2026-07-17T15:32:30Z",
  "published": "2026-07-17T15:32:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-23578"
    },
    {
      "type": "WEB",
      "url": "https://support.hcl-software.com/csm?id=kb_article\u0026sysparm_article=KB0132294"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G89M-R2GH-92R6

Vulnerability from github – Published: 2023-02-15 21:30 – Updated: 2023-02-24 18:30
VLAI
Details

Media CP Media Control Panel latest version. A Permissive Flash Cross-domain Policy may allow information disclosure.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-23464"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-02-15T19:15:00Z",
    "severity": "HIGH"
  },
  "details": "Media CP Media Control Panel latest version. A Permissive Flash Cross-domain Policy may allow information disclosure.",
  "id": "GHSA-g89m-r2gh-92r6",
  "modified": "2023-02-24T18:30:27Z",
  "published": "2023-02-15T21:30:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-23464"
    },
    {
      "type": "WEB",
      "url": "https://www.gov.il/en/Departments/faq/cve_advisories"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G9RG-8VQ5-MPWM

Vulnerability from github – Published: 2026-03-07 02:12 – Updated: 2026-03-20 21:32
VLAI
Summary
mcp-memory-service's Wildcard CORS with Credentials Enables Cross-Origin Memory Theft
Details

Summary

When the HTTP server is enabled (MCP_HTTP_ENABLED=true), the application configures FastAPI's CORSMiddleware with allow_origins=['*'], allow_credentials=True, allow_methods=["*"], and allow_headers=["*"]. The wildcard Access-Control-Allow-Origin: * header permits any website to read API responses cross-origin. When combined with anonymous access (MCP_ALLOW_ANONYMOUS_ACCESS=true) - the simplest way to get the HTTP dashboard working without OAuth - no credentials are needed, so any malicious website can silently read, modify, and delete all stored memories.

Details

Vulnerable Code

config.py:546 - Wildcard CORS origin default

CORS_ORIGINS = os.getenv('MCP_CORS_ORIGINS', '*').split(',')

This produces ['*'] by default, allowing any origin.

app.py:274-280 - CORSMiddleware configuration

# CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=CORS_ORIGINS,        # ['*'] by default
    allow_credentials=True,             # Unnecessary for anonymous access; bad practice
    allow_methods=["*"],
    allow_headers=["*"],
)

How the Attack Works

The wildcard CORS default means every API response includes Access-Control-Allow-Origin: *. This tells browsers to allow any website to read the response. When combined with anonymous access (no authentication required), the attack is straightforward:

// Running on https://evil.com - reads victim's memories
// No credentials needed - anonymous access means the API is open
const response = await fetch('http://192.168.1.100:8000/api/memories');
const memories = await response.json();
// memories contains every stored memory - passwords, API keys, personal notes

The browser sends the request, the server responds with ACAO: *, and the browser allows the JavaScript to read the response body. No cookies, no auth headers, no credentials of any kind.

Clarification on allow_credentials=True: The advisory originally stated that Starlette reflects the Origin header when allow_credentials=True with wildcard origins. Testing with Starlette 0.52.1 shows that actual responses return ACAO: * (not the reflected origin); only preflight OPTIONS responses reflect the origin. Per the Fetch specification, browsers block ACAO: * when credentials: 'include' is used. However, this is irrelevant to the attack because anonymous access means no credentials are needed - a plain fetch() without credentials: 'include' works, and ACAO: * allows it.

Two Attack Vectors

This misconfiguration enables two distinct attack paths:

1. Cross-origin browser attack (CORS - this advisory) - Attacker lures victim to a malicious webpage - JavaScript on the page reads/writes the memory service API - Works from anywhere on the internet if the victim visits the page - The ACAO: * header is what allows the browser to expose the response to the attacker's JavaScript

2. Direct network access (compounding factor) - Attacker on the same network directly calls the API (curl http://<target>:8000/api/memories) - No CORS involved - CORS is a browser-only restriction - Enabled by 0.0.0.0 binding + anonymous access, independent of CORS configuration

The CORS misconfiguration specifically enables attack vector #1, extending the reach from local network to anyone who can get the victim to click a link.

Compounding Factors

  • HTTP_HOST = '0.0.0.0' - Binds to all interfaces, exposing the service to the entire network (enables attack vector #2)
  • HTTPS_ENABLED = 'false' - No TLS by default, allowing passive interception
  • MCP_ALLOW_ANONYMOUS_ACCESS - When enabled, no authentication is required at all. This is the key enabler: without it, the CORS wildcard alone would not allow data access (the attacker would need to forward valid credentials, which ACAO: * blocks)
  • allow_credentials=True - Bad practice: if a future Starlette version changes to reflect origins (as some CORS implementations do), this would escalate the vulnerability by allowing credential-forwarding attacks against OAuth/API-key users
  • API key via query parameter - api_key query param is cached in browser history and server logs

Attack Scenario

  1. Victim runs mcp-memory-service with HTTP enabled and anonymous access
  2. Victim visits https://evil.com which includes JavaScript
  3. JavaScript sends fetch('http://<victim-ip>:8000/api/memories') (no credentials needed)
  4. Server responds with Access-Control-Allow-Origin: *
  5. Browser allows JavaScript to read the response - attacker receives all memories
  6. Attacker's script also calls DELETE/PUT endpoints to modify or destroy memories
  7. Victim sees a normal web page; no indication of the attack

Root Cause

The default value of MCP_CORS_ORIGINS is *, which allows any website to read API responses. This is a permissive default that should be restricted to the expected dashboard origin (typically localhost). The allow_credentials=True is an additional misconfiguration that doesn't currently enable the attack.

PoC

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from starlette.testclient import TestClient

app = FastAPI()
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

@app.get("/api/memories")
def memories():
    return [{"content": "secret memory data"}]

client = TestClient(app)

# Non-credentialed request (how the real attack works with anonymous access)
response = client.get("/api/memories", headers={"Origin": "https://evil.com"})
print(response.headers["access-control-allow-origin"])  # *
print(response.json())  # [{"content": "secret memory data"}]
# Any website can read this response because ACAO is *

Impact

  • Complete cross-origin memory access: Any website can read all stored memories when the victim has the HTTP server running with anonymous access
  • Memory tampering: Write/delete endpoints are also accessible cross-origin, allowing memory destruction
  • Remote attack surface: Unlike direct network access (which requires LAN proximity), the CORS vector works from anywhere on the internet - the victim just needs to visit a link
  • Silent exfiltration: The attack is invisible to the victim; no browser warnings, no popups, no indicators

Remediation

Replace the wildcard default with an explicit localhost origin:

# In config.py  (safe default)
CORS_ORIGINS = os.getenv('MCP_CORS_ORIGINS', 'http://localhost:8000,http://127.0.0.1:8000').split(',')

# In app.py - warn on wildcard
if '*' in CORS_ORIGINS:
    logger.warning("Wildcard CORS origin detected. This allows any website to access the API. "
                    "Set MCP_CORS_ORIGINS to restrict access.")

# Also: set allow_credentials=False unless specific origins are configured
app.add_middleware(
    CORSMiddleware,
    allow_origins=CORS_ORIGINS,
    allow_credentials='*' not in CORS_ORIGINS,  # Only with explicit origins
    allow_methods=["*"],
    allow_headers=["*"],
)

Affected Deployments

The vulnerability exists in the Python source code and is not mitigated by any deployment-specific configuration. Docker HTTP mode is the highest-risk deployment because it explicitly binds to 0.0.0.0, maps the port, and does not override the wildcard CORS default.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "mcp-memory-service"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.25.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33010"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-07T02:12:26Z",
    "nvd_published_at": "2026-03-20T19:16:17Z",
    "severity": "HIGH"
  },
  "details": "### Summary\nWhen the HTTP server is enabled (`MCP_HTTP_ENABLED=true`), the application configures FastAPI\u0027s CORSMiddleware with `allow_origins=[\u0027*\u0027]`, `allow_credentials=True`, `allow_methods=[\"*\"]`, and `allow_headers=[\"*\"]`. The wildcard `Access-Control-Allow-Origin: *` header permits any website to read API responses cross-origin. When combined with anonymous access (`MCP_ALLOW_ANONYMOUS_ACCESS=true`) - the simplest way to get the HTTP dashboard working without OAuth - no credentials are needed, so any malicious website can silently read, modify, and delete all stored memories.\n\n\n### Details\n### Vulnerable Code\n\n**`config.py:546` - Wildcard CORS origin default**\n\n```python\nCORS_ORIGINS = os.getenv(\u0027MCP_CORS_ORIGINS\u0027, \u0027*\u0027).split(\u0027,\u0027)\n```\n\nThis produces `[\u0027*\u0027]` by default, allowing any origin.\n\n**`app.py:274-280` - CORSMiddleware configuration**\n\n```python\n# CORS middleware\napp.add_middleware(\n    CORSMiddleware,\n    allow_origins=CORS_ORIGINS,        # [\u0027*\u0027] by default\n    allow_credentials=True,             # Unnecessary for anonymous access; bad practice\n    allow_methods=[\"*\"],\n    allow_headers=[\"*\"],\n)\n```\n\n### How the Attack Works\n\nThe wildcard CORS default means every API response includes `Access-Control-Allow-Origin: *`. This tells browsers to allow **any website** to read the response. When combined with anonymous access (no authentication required), the attack is straightforward:\n\n```javascript\n// Running on https://evil.com - reads victim\u0027s memories\n// No credentials needed - anonymous access means the API is open\nconst response = await fetch(\u0027http://192.168.1.100:8000/api/memories\u0027);\nconst memories = await response.json();\n// memories contains every stored memory - passwords, API keys, personal notes\n```\n\nThe browser sends the request, the server responds with `ACAO: *`, and the browser allows the JavaScript to read the response body. No cookies, no auth headers, no credentials of any kind.\n\n**Clarification on `allow_credentials=True`:** The advisory originally stated that Starlette reflects the `Origin` header when `allow_credentials=True` with wildcard origins. Testing with Starlette 0.52.1 shows that **actual responses return `ACAO: *`** (not the reflected origin); only preflight `OPTIONS` responses reflect the origin. Per the Fetch specification, browsers block `ACAO: *` when `credentials: \u0027include\u0027` is used. However, this is irrelevant to the attack because **anonymous access means no credentials are needed** - a plain `fetch()` without `credentials: \u0027include\u0027` works, and `ACAO: *` allows it.\n\n### Two Attack Vectors\n\nThis misconfiguration enables two distinct attack paths:\n\n**1. Cross-origin browser attack (CORS - this advisory)**\n- Attacker lures victim to a malicious webpage\n- JavaScript on the page reads/writes the memory service API\n- Works from anywhere on the internet if the victim visits the page\n- The `ACAO: *` header is what allows the browser to expose the response to the attacker\u0027s JavaScript\n\n**2. Direct network access (compounding factor)**\n- Attacker on the same network directly calls the API (`curl http://\u003ctarget\u003e:8000/api/memories`)\n- No CORS involved - CORS is a browser-only restriction\n- Enabled by `0.0.0.0` binding + anonymous access, independent of CORS configuration\n\nThe CORS misconfiguration specifically enables attack vector #1, extending the reach from local network to anyone who can get the victim to click a link.\n\n### Compounding Factors\n\n- **`HTTP_HOST = \u00270.0.0.0\u0027`** - Binds to all interfaces, exposing the service to the entire network (enables attack vector #2)\n- **`HTTPS_ENABLED = \u0027false\u0027`** - No TLS by default, allowing passive interception\n- **`MCP_ALLOW_ANONYMOUS_ACCESS`** - When enabled, no authentication is required at all. This is the key enabler: without it, the CORS wildcard alone would not allow data access (the attacker would need to forward valid credentials, which `ACAO: *` blocks)\n- **`allow_credentials=True`** - Bad practice: if a future Starlette version changes to reflect origins (as some CORS implementations do), this would escalate the vulnerability by allowing credential-forwarding attacks against OAuth/API-key users\n- **API key via query parameter** - `api_key` query param is cached in browser history and server logs\n\n### Attack Scenario\n\n1. Victim runs `mcp-memory-service` with HTTP enabled and anonymous access\n2. Victim visits `https://evil.com` which includes JavaScript\n3. JavaScript sends `fetch(\u0027http://\u003cvictim-ip\u003e:8000/api/memories\u0027)` (no credentials needed)\n4. Server responds with `Access-Control-Allow-Origin: *`\n5. Browser allows JavaScript to read the response - attacker receives all memories\n6. Attacker\u0027s script also calls DELETE/PUT endpoints to modify or destroy memories\n7. Victim sees a normal web page; no indication of the attack\n\n### Root Cause\n\nThe default value of `MCP_CORS_ORIGINS` is `*`, which allows any website to read API responses. This is a permissive default that should be restricted to the expected dashboard origin (typically `localhost`). The `allow_credentials=True` is an additional misconfiguration that doesn\u0027t currently enable the attack.\n\n\n### PoC\n```python\nfrom fastapi import FastAPI\nfrom fastapi.middleware.cors import CORSMiddleware\nfrom starlette.testclient import TestClient\n\napp = FastAPI()\napp.add_middleware(\n    CORSMiddleware,\n    allow_origins=[\"*\"],\n    allow_credentials=True,\n    allow_methods=[\"*\"],\n    allow_headers=[\"*\"],\n)\n\n@app.get(\"/api/memories\")\ndef memories():\n    return [{\"content\": \"secret memory data\"}]\n\nclient = TestClient(app)\n\n# Non-credentialed request (how the real attack works with anonymous access)\nresponse = client.get(\"/api/memories\", headers={\"Origin\": \"https://evil.com\"})\nprint(response.headers[\"access-control-allow-origin\"])  # *\nprint(response.json())  # [{\"content\": \"secret memory data\"}]\n# Any website can read this response because ACAO is *\n```\n\n\n### Impact\n- **Complete cross-origin memory access**: Any website can read all stored memories when the victim has the HTTP server running with anonymous access\n- **Memory tampering**: Write/delete endpoints are also accessible cross-origin, allowing memory destruction\n- **Remote attack surface**: Unlike direct network access (which requires LAN proximity), the CORS vector works from anywhere on the internet - the victim just needs to visit a link\n- **Silent exfiltration**: The attack is invisible to the victim; no browser warnings, no popups, no indicators\n\n## Remediation\n\nReplace the wildcard default with an explicit localhost origin:\n\n```python\n# In config.py  (safe default)\nCORS_ORIGINS = os.getenv(\u0027MCP_CORS_ORIGINS\u0027, \u0027http://localhost:8000,http://127.0.0.1:8000\u0027).split(\u0027,\u0027)\n\n# In app.py - warn on wildcard\nif \u0027*\u0027 in CORS_ORIGINS:\n    logger.warning(\"Wildcard CORS origin detected. This allows any website to access the API. \"\n                    \"Set MCP_CORS_ORIGINS to restrict access.\")\n\n# Also: set allow_credentials=False unless specific origins are configured\napp.add_middleware(\n    CORSMiddleware,\n    allow_origins=CORS_ORIGINS,\n    allow_credentials=\u0027*\u0027 not in CORS_ORIGINS,  # Only with explicit origins\n    allow_methods=[\"*\"],\n    allow_headers=[\"*\"],\n)\n```\n\n## Affected Deployments\nThe vulnerability exists in the Python source code and is not mitigated by any deployment-specific configuration. Docker HTTP mode is the highest-risk deployment because it explicitly binds to `0.0.0.0`, maps the port, and does not override the wildcard CORS default.",
  "id": "GHSA-g9rg-8vq5-mpwm",
  "modified": "2026-03-20T21:32:22Z",
  "published": "2026-03-07T02:12:26Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/doobidoo/mcp-memory-service/security/advisories/GHSA-g9rg-8vq5-mpwm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33010"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/doobidoo/mcp-memory-service"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "mcp-memory-service\u0027s Wildcard CORS with Credentials Enables Cross-Origin Memory Theft"
}

GHSA-GFC2-9QMW-W7VH

Vulnerability from github – Published: 2026-04-21 15:14 – Updated: 2026-05-04 20:08
VLAI
Summary
Glances: Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS
Details

Summary

The Glances web server exposes a REST API (/api/4/*) that is accessible without authentication and allows cross-origin requests from any origin due to a permissive CORS policy (Access-Control-Allow-Origin: *).

This allows a malicious website to read sensitive system information from a running Glances instance in the victim’s browser, leading to cross-origin data exfiltration.

While a previous advisory exists for XML-RPC CORS issues, this report demonstrates that the REST API (/api/4/*) is also affected and exposes significantly more sensitive data.

Details

When Glances is started in web mode (e.g., glances -w -B 0.0.0.0), it exposes a REST API endpoint at: http://:61208/api/4/all The server responds with: Access-Control-Allow-Origin: *

This allows any origin to perform cross-origin requests and read responses.

The /api/4/all endpoint returns extensive system information, including: - Process list (processlist) - System details (hostname, OS, CPU info) - Memory and disk usage - Network interfaces and IP address - Running services and metrics Because no authentication is required by default, this data is accessible to any web page.

PoC

  1. Start Glances: glances -w -B 0.0.0.0

  2. Create a malicious HTML file:

<!DOCTYPE html>
<html>
<body>
<script>
fetch("http://<victim-ip>:61208/api/4/all")
  .then(r => r.json())
  .then(data => {
    console.log("DATA:", data);
  });
</script>
</body>
</html>
  1. Open the file in a browser while Glances is running.
  2. Observe that the browser successfully retrieves sensitive system information from the API. This works cross-origin (e.g., from file:// or attacker-controlled domains).

Impact

A remote attacker can host a malicious website that, when visited by a victim running Glances, can:

  • Read sensitive system information
  • Enumerate running processes
  • Identify network configuration and IP addresses
  • Fingerprint the host system

This requires no authentication and no user interaction beyond visiting a web page. This represents a cross-origin information disclosure vulnerability and can aid further attacks such as reconnaissance or targeted exploitation.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "Glances"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.5.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34839"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-200",
      "CWE-306",
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-21T15:14:40Z",
    "nvd_published_at": "2026-04-21T00:16:27Z",
    "severity": "HIGH"
  },
  "details": "### Summary\nThe Glances web server exposes a REST API (`/api/4/*`) that is accessible without authentication and allows cross-origin requests from any origin due to a permissive CORS policy (`Access-Control-Allow-Origin: *`).\n\nThis allows a malicious website to read sensitive system information from a running Glances instance in the victim\u2019s browser, leading to cross-origin data exfiltration.\n\nWhile a previous advisory exists for XML-RPC CORS issues, this report demonstrates that the REST API (`/api/4/*`) is also affected and exposes significantly more sensitive data.\n\n### Details\nWhen Glances is started in web mode (e.g., `glances -w -B 0.0.0.0`), it exposes a REST API endpoint at:\nhttp://\u003chost\u003e:61208/api/4/all\nThe server responds with:\nAccess-Control-Allow-Origin: *\n\nThis allows any origin to perform cross-origin requests and read responses.\n\nThe `/api/4/all` endpoint returns extensive system information, including:\n- Process list (`processlist`)\n- System details (hostname, OS, CPU info)\n- Memory and disk usage\n- Network interfaces and IP address\n- Running services and metrics\nBecause no authentication is required by default, this data is accessible to any web page.\n\n### PoC\n1. Start Glances:\nglances -w -B 0.0.0.0\n\n2. Create a malicious HTML file:\n\n```\n\u003c!DOCTYPE html\u003e\n\u003chtml\u003e\n\u003cbody\u003e\n\u003cscript\u003e\nfetch(\"http://\u003cvictim-ip\u003e:61208/api/4/all\")\n  .then(r =\u003e r.json())\n  .then(data =\u003e {\n    console.log(\"DATA:\", data);\n  });\n\u003c/script\u003e\n\u003c/body\u003e\n\u003c/html\u003e\n```\n2. Open the file in a browser while Glances is running.\n3. Observe that the browser successfully retrieves sensitive system information from the API.\nThis works cross-origin (e.g., from file:// or attacker-controlled domains).\n\n### Impact\nA remote attacker can host a malicious website that, when visited by a victim running Glances, can:\n\n- Read sensitive system information\n- Enumerate running processes\n- Identify network configuration and IP addresses\n- Fingerprint the host system\n\nThis requires no authentication and no user interaction beyond visiting a web page. This represents a cross-origin information disclosure vulnerability and can aid further attacks such as reconnaissance or targeted exploitation.",
  "id": "GHSA-gfc2-9qmw-w7vh",
  "modified": "2026-05-04T20:08:23Z",
  "published": "2026-04-21T15:14:40Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nicolargo/glances/security/advisories/GHSA-gfc2-9qmw-w7vh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34839"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nicolargo/glances/commit/fdfb977b1d91b5e410bc06c4e19f8bedb0005ce9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/nicolargo/glances"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Glances: Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS"
}

GHSA-GJV7-4R9P-7HMX

Vulnerability from github – Published: 2026-03-31 12:31 – Updated: 2026-03-31 12:31
VLAI
Details

When the internal webserver is enabled (default is disabled), an attacker might be able to trick an administrator logged to the dashboard into visiting a malicious website and extract information about the running configuration from the dashboard. The root cause of the issue is a misconfiguration of the Cross-Origin Resource Sharing (CORS) policy.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-0397"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-31T12:16:27Z",
    "severity": "LOW"
  },
  "details": "When the internal webserver is enabled (default is disabled), an attacker might be able to trick an administrator logged to the dashboard into visiting a malicious website and extract information about the running configuration from the dashboard. The root cause of the issue is a misconfiguration of the Cross-Origin Resource Sharing (CORS) policy.",
  "id": "GHSA-gjv7-4r9p-7hmx",
  "modified": "2026-03-31T12:31:35Z",
  "published": "2026-03-31T12:31:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0397"
    },
    {
      "type": "WEB",
      "url": "https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-02.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-H4X5-FMW9-97F9

Vulnerability from github – Published: 2026-07-17 03:31 – Updated: 2026-07-17 03:31
VLAI
Details

The Grav API plugin (getgrav/grav-plugin-api) before 1.0.0-rc.16 shipped Access-Control-Allow-Origin: * as its default CORS configuration on all responses, including authenticated endpoints and preflight (OPTIONS) responses. Because the plugin accepts credentials via the Authorization and X-API-Token headers (set programmatically by JavaScript rather than via cookies), an attacker who obtains a valid access token (e.g., via log leakage, Referer headers, browser history, or network capture) can issue fully authenticated cross-origin requests from any malicious website to read sensitive data and perform write operations as the token's user. Fixed in 1.0.0-rc.16.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-62387"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-17T02:18:12Z",
    "severity": "HIGH"
  },
  "details": "The Grav API plugin (getgrav/grav-plugin-api) before 1.0.0-rc.16 shipped Access-Control-Allow-Origin: * as its default CORS configuration on all responses, including authenticated endpoints and preflight (OPTIONS) responses. Because the plugin accepts credentials via the Authorization and X-API-Token headers (set programmatically by JavaScript rather than via cookies), an attacker who obtains a valid access token (e.g., via log leakage, Referer headers, browser history, or network capture) can issue fully authenticated cross-origin requests from any malicious website to read sensitive data and perform write operations as the token\u0027s user. Fixed in 1.0.0-rc.16.",
  "id": "GHSA-h4x5-fmw9-97f9",
  "modified": "2026-07-17T03:31:24Z",
  "published": "2026-07-17T03:31:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/getgrav/grav/security/advisories/GHSA-93px-98wh-6fj2"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-62387"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/grav-rc-16-cors-misconfiguration-via-api-plugin"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

Mitigation
Architecture and Design Operation

Strategy: Attack Surface Reduction

Define a restrictive Content Security Policy [REF-1486] or cross-domain policy file.

Mitigation
Architecture and Design Operation

Strategy: Attack Surface Reduction

Avoid using wildcards in the CSP / cross-domain policy file. Any domain matching the wildcard expression will be implicitly trusted, and can perform two-way interaction with the target server.

Mitigation
Architecture and Design Operation

Strategy: Environment Hardening

For Flash, modify crossdomain.xml to use meta-policy options such as 'master-only' or 'none' to reduce the possibility of an attacker planting extraneous cross-domain policy files on a server.

No CAPEC attack patterns related to this CWE.