CWE-601
AllowedURL Redirection to Untrusted Site ('Open Redirect')
Abstraction: Base · Status: Draft
The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.
2310 vulnerabilities reference this CWE, most recent first.
GHSA-GW8W-QW5V-VJ6C
Vulnerability from github – Published: 2023-07-26 21:30 – Updated: 2024-04-04 06:22Netdisco before v2.063000 was discovered to contain an open redirect vulnerability. An attacker may exploit this vulnerability to redirect users to arbitrary web URLs by tricking the victim users to click on crafted links.
{
"affected": [],
"aliases": [
"CVE-2023-37624"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-07-26T20:15:12Z",
"severity": "MODERATE"
},
"details": "Netdisco before v2.063000 was discovered to contain an open redirect vulnerability. An attacker may exploit this vulnerability to redirect users to arbitrary web URLs by tricking the victim users to click on crafted links.",
"id": "GHSA-gw8w-qw5v-vj6c",
"modified": "2024-04-04T06:22:16Z",
"published": "2023-07-26T21:30:19Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-37624"
},
{
"type": "WEB",
"url": "https://github.com/netdisco/netdisco/commit/a2da6a7a046c1c0fd41072dd6991eec7614293f8"
},
{
"type": "WEB",
"url": "https://github.com/benjaminpsinclair/Netdisco-2023-Advisory"
},
{
"type": "WEB",
"url": "https://github.com/benjaminpsinclair/Netdisco-CVE"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-GWFG-4782-GV5M
Vulnerability from github – Published: 2022-05-11 00:01 – Updated: 2022-05-17 00:00The Ultimate Member plugin for WordPress is vulnerable to open redirects due to insufficient validation on supplied URLs in the social fields of the Profile Page, which makes it possible for attackers to redirect unsuspecting victims in versions up to, and including, 2.3.1 granted the victim clicks on a social icon on a user's profile page.
{
"affected": [],
"aliases": [
"CVE-2022-1209"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-05-10T20:15:00Z",
"severity": "MODERATE"
},
"details": "The Ultimate Member plugin for WordPress is vulnerable to open redirects due to insufficient validation on supplied URLs in the social fields of the Profile Page, which makes it possible for attackers to redirect unsuspecting victims in versions up to, and including, 2.3.1 granted the victim clicks on a social icon on a user\u0027s profile page.",
"id": "GHSA-gwfg-4782-gv5m",
"modified": "2022-05-17T00:00:59Z",
"published": "2022-05-11T00:01:13Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-1209"
},
{
"type": "WEB",
"url": "https://github.com/ultimatemember/ultimatemember/issues/989"
},
{
"type": "WEB",
"url": "https://github.com/ultimatemember/ultimatemember/pull/990"
},
{
"type": "WEB",
"url": "https://github.com/H4de5-7/vulnerabilities/blob/main/Ultimate%20Member%20%3C%3D%202.3.1%20-%20Open%20Redirect.md"
},
{
"type": "WEB",
"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d638120b-5396-408b-8273-d003ff9dd01d?source=cve"
},
{
"type": "WEB",
"url": "https://www.wordfence.com/vulnerability-advisories/#CVE-2022-1209"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-GWP7-VQR5-H33H
Vulnerability from github – Published: 2021-04-20 16:13 – Updated: 2024-09-04 19:35Autobahn|Python before 20.12.3 allows redirect header injection.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "autobahn"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "20.12.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-35678"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2021-04-07T22:27:56Z",
"nvd_published_at": "2020-12-27T00:15:00Z",
"severity": "MODERATE"
},
"details": "Autobahn|Python before 20.12.3 allows redirect header injection.",
"id": "GHSA-gwp7-vqr5-h33h",
"modified": "2024-09-04T19:35:17Z",
"published": "2021-04-20T16:13:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-35678"
},
{
"type": "WEB",
"url": "https://github.com/crossbario/autobahn-python/pull/1439"
},
{
"type": "WEB",
"url": "https://autobahn.readthedocs.io/en/latest/changelog.html"
},
{
"type": "PACKAGE",
"url": "https://github.com/crossbario/autobahn-python"
},
{
"type": "WEB",
"url": "https://github.com/crossbario/autobahn-python/compare/v20.12.2...v20.12.3"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/autobahn/PYSEC-2020-25.yaml"
},
{
"type": "WEB",
"url": "https://pypi.org/project/autobahn/20.12.3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Open Redirect in autobahn"
}
GHSA-GWVM-45GX-3CF8
Vulnerability from github – Published: 2023-10-15 21:30 – Updated: 2024-11-18 23:15urllib3 before 1.24.2 does not remove the authorization HTTP header when following a cross-origin redirect (i.e., a redirect that differs in host, port, or scheme). This can allow for credentials in the authorization header to be exposed to unintended hosts or transmitted in cleartext. NOTE: this issue exists because of an incomplete fix for CVE-2018-20060 (which was case-sensitive).
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "urllib3"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.24.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2018-25091"
],
"database_specific": {
"cwe_ids": [
"CWE-200",
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2023-10-17T14:21:39Z",
"nvd_published_at": "2023-10-15T19:15:09Z",
"severity": "MODERATE"
},
"details": "urllib3 before 1.24.2 does not remove the authorization HTTP header when following a cross-origin redirect (i.e., a redirect that differs in host, port, or scheme). This can allow for credentials in the authorization header to be exposed to unintended hosts or transmitted in cleartext. NOTE: this issue exists because of an incomplete fix for CVE-2018-20060 (which was case-sensitive).",
"id": "GHSA-gwvm-45gx-3cf8",
"modified": "2024-11-18T23:15:14Z",
"published": "2023-10-15T21:30:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-25091"
},
{
"type": "WEB",
"url": "https://github.com/urllib3/urllib3/issues/1510"
},
{
"type": "WEB",
"url": "https://github.com/urllib3/urllib3/commit/adb358f8e06865406d1f05e581a16cbea2136fbc"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/urllib3/PYSEC-2023-207.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/urllib3/urllib3"
},
{
"type": "WEB",
"url": "https://github.com/urllib3/urllib3/compare/1.24.1...1.24.2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Authorization Header forwarded on redirect"
}
GHSA-GX8M-4376-PV8M
Vulnerability from github – Published: 2022-05-24 17:33 – Updated: 2022-05-24 17:33touchbase.ai before version 2.0 is vulnerable to Open Redirect. Impacts can be many, and vary from theft of information and credentials, to the redirection to malicious websites containing attacker-controlled content, which in some cases even cause XSS attacks. So even though an open redirection might sound harmless at first, the impacts of it can be severe should it be exploitable. The issue is fixed in version 2.0.
{
"affected": [],
"aliases": [
"CVE-2020-26219"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-11-11T22:15:00Z",
"severity": "MODERATE"
},
"details": "touchbase.ai before version 2.0 is vulnerable to Open Redirect. Impacts can be many, and vary from theft of information and credentials, to the redirection to malicious websites containing attacker-controlled content, which in some cases even cause XSS attacks. So even though an open redirection might sound harmless at first, the impacts of it can be severe should it be exploitable. The issue is fixed in version 2.0.",
"id": "GHSA-gx8m-4376-pv8m",
"modified": "2022-05-24T17:33:58Z",
"published": "2022-05-24T17:33:58Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/puncsky/touchbase.ai/security/advisories/GHSA-6wcq-7r33-gw8x"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-26219"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-GXJJ-F44V-QM94
Vulnerability from github – Published: 2021-12-14 18:14 – Updated: 2021-12-14 18:14Withdrawn
Duplicate of GHSA-6qmf-fj6m-686c
Original description
Flask-Security-Too 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 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`.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "Flask-Security-Too"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "4.0.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2021-05-19T17:52:04Z",
"nvd_published_at": null,
"severity": "LOW"
},
"details": "# Withdrawn\n\nDuplicate of GHSA-6qmf-fj6m-686c\n\n# Original description\n\nFlask-Security-Too 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 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`.",
"id": "GHSA-gxjj-f44v-qm94",
"modified": "2021-12-14T18:14:54Z",
"published": "2021-12-14T18:14:04Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/Flask-Middleware/flask-security/security/advisories/GHSA-6qmf-fj6m-686c"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32618"
},
{
"type": "WEB",
"url": "https://github.com/Flask-Middleware/flask-security/issues/486"
}
],
"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"
}
],
"summary": "Open Redirect in Flask-Security-Too",
"withdrawn": "2021-05-27T19:07:52Z"
}
GHSA-GXQC-9W8X-48V5
Vulnerability from github – Published: 2025-04-16 15:34 – Updated: 2026-04-01 18:34URL Redirection to Untrusted Site ('Open Redirect') vulnerability in Arthur Yarwood Fast eBay Listings allows Phishing. This issue affects Fast eBay Listings: from n/a through 2.12.15.
{
"affected": [],
"aliases": [
"CVE-2025-39597"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-04-16T13:15:52Z",
"severity": "MODERATE"
},
"details": "URL Redirection to Untrusted Site (\u0027Open Redirect\u0027) vulnerability in Arthur Yarwood Fast eBay Listings allows Phishing. This issue affects Fast eBay Listings: from n/a through 2.12.15.",
"id": "GHSA-gxqc-9w8x-48v5",
"modified": "2026-04-01T18:34:45Z",
"published": "2025-04-16T15:34:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39597"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/wordpress/plugin/fast-ebay-listings/vulnerability/wordpress-fast-ebay-listings-2-12-15-open-redirection-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-GXRQ-7HVQ-53Q3
Vulnerability from github – Published: 2022-02-15 00:02 – Updated: 2022-02-24 00:01The WordPress Newsletter Plugin WordPress plugin before 1.6.5 does not validate the to parameter before redirecting the user to its given value, leading to an open redirect issue
{
"affected": [],
"aliases": [
"CVE-2021-25033"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-02-14T12:15:00Z",
"severity": "MODERATE"
},
"details": "The WordPress Newsletter Plugin WordPress plugin before 1.6.5 does not validate the to parameter before redirecting the user to its given value, leading to an open redirect issue",
"id": "GHSA-gxrq-7hvq-53q3",
"modified": "2022-02-24T00:01:13Z",
"published": "2022-02-15T00:02:49Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-25033"
},
{
"type": "WEB",
"url": "https://plugins.trac.wordpress.org/changeset/2639592"
},
{
"type": "WEB",
"url": "https://wpscan.com/vulnerability/c2d2384c-41b9-4aaf-b918-c1cfda58af5c"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-GXWX-C7M8-F95H
Vulnerability from github – Published: 2022-05-17 03:56 – Updated: 2024-04-23 22:19Open redirect vulnerability in the drupal_goto function in Drupal 6.x before 6.38, when used with PHP before 5.4.7, allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a double-encoded URL in the "destination" parameter.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "drupal/core"
},
"ranges": [
{
"events": [
{
"introduced": "6.0"
},
{
"fixed": "6.38"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Packagist",
"name": "drupal/drupal"
},
"ranges": [
{
"events": [
{
"introduced": "6.0"
},
{
"fixed": "6.38"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2016-3167"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2024-04-23T22:19:04Z",
"nvd_published_at": "2016-04-12T15:59:00Z",
"severity": "HIGH"
},
"details": "Open redirect vulnerability in the drupal_goto function in Drupal 6.x before 6.38, when used with PHP before 5.4.7, allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a double-encoded URL in the \"destination\" parameter.",
"id": "GHSA-gxwx-c7m8-f95h",
"modified": "2024-04-23T22:19:04Z",
"published": "2022-05-17T03:56:54Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2016-3167"
},
{
"type": "WEB",
"url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/drupal/core/CVE-2016-3167.yaml"
},
{
"type": "WEB",
"url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/drupal/drupal/CVE-2016-3167.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/drupal/core"
},
{
"type": "WEB",
"url": "https://www.drupal.org/SA-CORE-2016-001"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2016/dsa-3498"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2016/02/24/19"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2016/03/15/10"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Drupal Open redirect vulnerability in the drupal_goto function"
}
GHSA-GXXW-7M39-6FJM
Vulnerability from github – Published: 2024-06-27 21:32 – Updated: 2024-06-27 21:32An open redirect vulnerability exists in imartinez/privategpt version 0.5.0 due to improper handling of the 'file' parameter. This vulnerability allows attackers to redirect users to a URL specified by user-controlled input without proper validation or sanitization. The impact of this vulnerability includes potential phishing attacks, malware distribution, and credential theft.
{
"affected": [],
"aliases": [
"CVE-2024-5936"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-27T19:15:18Z",
"severity": "MODERATE"
},
"details": "An open redirect vulnerability exists in imartinez/privategpt version 0.5.0 due to improper handling of the \u0027file\u0027 parameter. This vulnerability allows attackers to redirect users to a URL specified by user-controlled input without proper validation or sanitization. The impact of this vulnerability includes potential phishing attacks, malware distribution, and credential theft.",
"id": "GHSA-gxxw-7m39-6fjm",
"modified": "2024-06-27T21:32:08Z",
"published": "2024-06-27T21:32:08Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-5936"
},
{
"type": "WEB",
"url": "https://huntr.com/bounties/43f05c1e-d7b8-45e2-b1fe-48faf1e3a48d"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
Mitigation MIT-5
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- Use a list of approved URLs or domains to be used for redirection.
Mitigation
Use an intermediate disclaimer page that provides the user with a clear warning that they are leaving the current site. Implement a long timeout before the redirect occurs, or force the user to click on the link. Be careful to avoid XSS problems (CWE-79) when generating the disclaimer page.
Mitigation MIT-21.2
Strategy: Enforcement by Conversion
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
- For example, ID 1 could map to "/login.asp" and ID 2 could map to "http://www.example.com/". Features such as the ESAPI AccessReferenceMap [REF-45] provide this capability.
Mitigation
Ensure that no externally-supplied requests are honored by requiring that all redirect requests include a unique nonce generated by the application [REF-483]. Be sure that the nonce is not predictable (CWE-330).
Mitigation MIT-6
Strategy: Attack Surface Reduction
- Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
- Many open redirect problems occur because the programmer assumed that certain inputs could not be modified, such as cookies and hidden form fields.
Mitigation MIT-29
Strategy: Firewall
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
CAPEC-178: Cross-Site Flashing
An attacker is able to trick the victim into executing a Flash document that passes commands or calls to a Flash player browser plugin, allowing the attacker to exploit native Flash functionality in the client browser. This attack pattern occurs where an attacker can provide a crafted link to a Flash document (SWF file) which, when followed, will cause additional malicious instructions to be executed. The attacker does not need to serve or control the Flash document. The attack takes advantage of the fact that Flash files can reference external URLs. If variables that serve as URLs that the Flash application references can be controlled through parameters, then by creating a link that includes values for those parameters, an attacker can cause arbitrary content to be referenced and possibly executed by the targeted Flash application.