github - GHSA-6qmf-fj6m-686c

GHSA-6qmf-fj6m-686c

Vulnerability from github

Published

2021-05-17 20:51

Modified

2024-09-20 21:06

Severity ?

3.1 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
2.1 (Low) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Summary

Open Redirect in Flask-Security-Too

Details

Impact

Flask-Security allows redirects after many successful views (e.g. /login) by honoring the ?next query param. There is code in FS to validate that the url specified in the next parameter is either relative OR has the same netloc (network location) as the requesting URL.

This check utilizes Pythons urlsplit library. However many browsers are very lenient on the kind of URL they accept and 'fill in the blanks' when presented with a possibly incomplete URL. As a concrete example - setting http://login?next=\\github.com will pass FS's relative URL check however many browsers will gladly convert this to http://github.com. Thus an attacker could send such a link to an unwitting user, using a legitimate site and have it redirect to whatever site they want.

This is considered a low severity due to the fact that if Werkzeug by default ALWAYS ensures that the Location header is absolute - thus making this attack vector mute. It is possible for application writers to modify this default behavior by setting the 'autocorrect_location_header=False` which would then open up their application to this attack.

Patches

No patches as this time

Workarounds

If using Werkzeug, make sure to use the default Location header setting. If you can't - then use@app.after_request and write your own validation of the Location header if it is set.

References

No.

For more information

If you have any questions or comments about this advisory follow: https://github.com/Flask-Middleware/flask-security/issues/486

Thanks to Claroty (2021-0141) and @snoopysecurity for providing details and proof of concept.

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "Flask-Security-Too"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-32618"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-601"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-05-17T16:53:26Z",
    "nvd_published_at": null,
    "severity": "LOW"
  },
  "details": "### Impact\nFlask-Security allows redirects after many successful views (e.g. /login) by honoring the ?next query param. There is code in FS to validate that the url specified in the next parameter is either relative OR has the same netloc (network location) as the requesting  URL.\n\nThis check utilizes Pythons urlsplit library. However many browsers are very lenient on the kind of URL they accept and \u0027fill in the blanks\u0027 when presented with a possibly incomplete URL. As a concrete example - setting http://login?next=\\\\\\github.com\nwill pass FS\u0027s relative URL check however many browsers will gladly convert this to http://github.com. Thus an attacker could send such a link to an unwitting user, using a legitimate site and have it redirect to whatever site they want.\n\nThis is considered a low severity due to the fact that if Werkzeug by default ALWAYS ensures that the Location header is absolute - thus making this attack vector mute. It is possible for application writers to modify this default behavior by setting the \u0027autocorrect_location_header=False` which would then open up their application to this attack.\n\n### Patches\nNo patches as this time\n\n### Workarounds\nIf using Werkzeug, make sure to use the default Location header setting. If you can\u0027t - then use@app.after_request and write your own validation of the Location header if it is set.\n\n### References\nNo.\n\n### For more information\nIf you have any questions or comments about this advisory follow: https://github.com/Flask-Middleware/flask-security/issues/486\n\nThanks to Claroty (2021-0141) and @snoopysecurity for providing details and proof of concept.\n",
  "id": "GHSA-6qmf-fj6m-686c",
  "modified": "2024-09-20T21:06:55Z",
  "published": "2021-05-17T20:51:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32618"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Flask-Middleware/flask-security/commit/e39bb04615050448c1b8ba4caa7dacc0edd3e405"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Flask-Middleware/flask-security"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/flask-security-too/PYSEC-2021-123.yaml"
    },
    {
      "type": "WEB",
      "url": "https://web.archive.org/web/20210517211717/https://github.com/Flask-Middleware/flask-security/issues/486"
    },
    {
      "type": "WEB",
      "url": "https://web.archive.org/web/20211207121851/https://github.com/Flask-Middleware/flask-security/security/advisories/GHSA-6qmf-fj6m-686c"
    },
    {
      "type": "WEB",
      "url": "https://web.archive.org/web/20220410062740/https://github.com/Flask-Middleware/flask-security/pull/489"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Open Redirect in Flask-Security-Too"
}

cve-2021-32618

Vulnerability from cvelistv5

Published

2021-05-17 18:05

Modified

2024-08-03 23:25

Severity ?

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

Summary

The Python "Flask-Security-Too" package is used for adding security features to your Flask application. It is an is an independently maintained version of Flask-Security based on the 3.0.0 version of Flask-Security. All versions of Flask-Security-Too allow redirects after many successful views (e.g. /login) by honoring the ?next query param. There is code in FS to validate that the url specified in the next parameter is either relative OR has the same netloc (network location) as the requesting URL. This check utilizes Pythons urlsplit library. However many browsers are very lenient on the kind of URL they accept and 'fill in the blanks' when presented with a possibly incomplete URL. As a concrete example - setting http://login?next=\\\github.com will pass FS's relative URL check however many browsers will gladly convert this to http://github.com. Thus an attacker could send such a link to an unwitting user, using a legitimate site and have it redirect to whatever site they want. This is considered a low severity due to the fact that if Werkzeug is used (which is very common with Flask applications) as the WSGI layer, it by default ALWAYS ensures that the Location header is absolute - thus making this attack vector mute. It is possible for application writers to modify this default behavior by setting the 'autocorrect_location_header=False`.

References

▼	URL	Tags
	https://github.com/Flask-Middleware/flask-security/security/advisories/GHSA-6qmf-fj6m-686c	x_refsource_CONFIRM
	https://github.com/Flask-Middleware/flask-security/issues/486	x_refsource_MISC

Impacted products

Vendor

Product

Version

▼

Flask-Middleware

flask-security

Version: <= 4.0.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T23:25:30.629Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
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        "references": [
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            "tags": [
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            "url": "https://github.com/Flask-Middleware/flask-security/security/advisories/GHSA-6qmf-fj6m-686c"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/Flask-Middleware/flask-security/issues/486"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
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          "vendor": "Flask-Middleware",
          "versions": [
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        {
          "lang": "en",
          "value": "The Python \"Flask-Security-Too\" package is used for adding security features to your Flask application. It is an is an independently maintained version of Flask-Security based on the 3.0.0 version of Flask-Security. All versions of Flask-Security-Too allow redirects after many successful views (e.g. /login) by honoring the ?next query param. There is code in FS to validate that the url specified in the next parameter is either relative OR has the same netloc (network location) as the requesting URL. This check utilizes Pythons urlsplit library. However many browsers are very lenient on the kind of URL they accept and \u0027fill in the blanks\u0027 when presented with a possibly incomplete URL. As a concrete example - setting http://login?next=\\\\\\github.com will pass FS\u0027s relative URL check however many browsers will gladly convert this to http://github.com. Thus an attacker could send such a link to an unwitting user, using a legitimate site and have it redirect to whatever site they want. This is considered a low severity due to the fact that if Werkzeug is used (which is very common with Flask applications) as the WSGI layer, it by default ALWAYS ensures that the Location header is absolute - thus making this attack vector mute. It is possible for application writers to modify this default behavior by setting the \u0027autocorrect_location_header=False`."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.1,
            "baseSeverity": "LOW",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-601",
              "description": "CWE-601: URL Redirection to Untrusted Site (\u0027Open Redirect\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-05-17T18:05:10",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
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      "references": [
        {
          "tags": [
            "x_refsource_CONFIRM"
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            "x_refsource_MISC"
          ],
          "url": "https://github.com/Flask-Middleware/flask-security/issues/486"
        }
      ],
      "source": {
        "advisory": "GHSA-6qmf-fj6m-686c",
        "discovery": "UNKNOWN"
      },
      "title": "Open Redirect Vulnerability",
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security-advisories@github.com",
          "ID": "CVE-2021-32618",
          "STATE": "PUBLIC",
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        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "flask-security",
                      "version": {
                        "version_data": [
                          {
                            "version_value": "\u003c= 4.0.1"
                          }
                        ]
                      }
                    }
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                "vendor_name": "Flask-Middleware"
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        "data_type": "CVE",
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            }
          ]
        },
        "impact": {
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            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.1,
            "baseSeverity": "LOW",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N",
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            },
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    "dateUpdated": "2024-08-03T23:25:30.629Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

pysec-2021-123

Vulnerability from pysec

Published

2021-05-17 18:15

Modified

2021-08-25 04:30

Details

The Python "Flask-Security-Too" package is used for adding security features to your Flask application. It is an is an independently maintained version of Flask-Security based on the 3.0.0 version of Flask-Security. All versions of Flask-Security-Too allow redirects after many successful views (e.g. /login) by honoring the ?next query param. There is code in FS to validate that the url specified in the next parameter is either relative OR has the same netloc (network location) as the requesting URL. This check utilizes Pythons urlsplit library. However many browsers are very lenient on the kind of URL they accept and 'fill in the blanks' when presented with a possibly incomplete URL. As a concrete example - setting http://login?next=\\github.com will pass FS's relative URL check however many browsers will gladly convert this to http://github.com. Thus an attacker could send such a link to an unwitting user, using a legitimate site and have it redirect to whatever site they want. This is considered a low severity due to the fact that if Werkzeug is used (which is very common with Flask applications) as the WSGI layer, it by default ALWAYS ensures that the Location header is absolute - thus making this attack vector mute. It is possible for application writers to modify this default behavior by setting the autocorrect_location_header=False.

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "flask-security-too",
        "purl": "pkg:pypi/flask-security-too"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.1",
        "3.0.1rc1",
        "3.0.1rc2",
        "3.0.1rc3",
        "3.0.2",
        "3.1.0rc1",
        "3.2.0",
        "3.2.0rc1",
        "3.2.0rc3",
        "3.2.0rc4",
        "3.3.0",
        "3.3.0rc1",
        "3.3.0rc2",
        "3.3.0rc3",
        "3.3.1",
        "3.3.2",
        "3.3.3",
        "3.4.0",
        "3.4.1",
        "3.4.2",
        "3.4.3",
        "3.4.4",
        "3.4.5",
        "4.0.0",
        "4.0.0rc1",
        "4.0.0rc2",
        "4.0.1"
      ]
    }
  ],
  "aliases": [
    "CVE-2021-32618",
    "GHSA-6qmf-fj6m-686c"
  ],
  "details": "The Python \"Flask-Security-Too\" package is used for adding security features to your Flask application. It is an is an independently maintained version of Flask-Security based on the 3.0.0 version of Flask-Security. All versions of Flask-Security-Too allow redirects after many successful views (e.g. /login) by honoring the ?next query param. There is code in FS to validate that the url specified in the next parameter is either relative OR has the same netloc (network location) as the requesting URL. This check utilizes Pythons urlsplit library. However many browsers are very lenient on the kind of URL they accept and \u0027fill in the blanks\u0027 when presented with a possibly incomplete URL. As a concrete example - setting http://login?next=\\\\\\github.com will pass FS\u0027s relative URL check however many browsers will gladly convert this to http://github.com. Thus an attacker could send such a link to an unwitting user, using a legitimate site and have it redirect to whatever site they want. This is considered a low severity due to the fact that if Werkzeug is used (which is very common with Flask applications) as the WSGI layer, it by default ALWAYS ensures that the Location header is absolute - thus making this attack vector mute. It is possible for application writers to modify this default behavior by setting the `autocorrect_location_header=False`.",
  "id": "PYSEC-2021-123",
  "modified": "2021-08-25T04:30:09.653075Z",
  "published": "2021-05-17T18:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://github.com/Flask-Middleware/flask-security/issues/486"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/Flask-Middleware/flask-security/security/advisories/GHSA-6qmf-fj6m-686c"
    }
  ]
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

Action not permitted

GHSA-6qmf-fj6m-686c

Vulnerability from github

Impact

Patches

Workarounds

References

For more information

cve-2021-32618

Vulnerability from cvelistv5

pysec-2021-123

Vulnerability from pysec

Tags

Sightings

Nomenclature