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.
2334 vulnerabilities reference this CWE, most recent first.
GHSA-FCGG-QGXG-2G2X
Vulnerability from github – Published: 2022-05-14 01:36 – Updated: 2024-09-13 19:33Open redirect vulnerability in EC-CUBE (EC-CUBE 3.0.0, EC-CUBE 3.0.1, EC-CUBE 3.0.2, EC-CUBE 3.0.3, EC-CUBE 3.0.4, EC-CUBE 3.0.5, EC-CUBE 3.0.6, EC-CUBE 3.0.7, EC-CUBE 3.0.8, EC-CUBE 3.0.9, EC-CUBE 3.0.10, EC-CUBE 3.0.11, EC-CUBE 3.0.12, EC-CUBE 3.0.12-p1, EC-CUBE 3.0.13, EC-CUBE 3.0.14, EC-CUBE 3.0.15, EC-CUBE 3.0.16) allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via unspecified vectors.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 3.0.16"
},
"package": {
"ecosystem": "Packagist",
"name": "ec-cube/ec-cube"
},
"ranges": [
{
"events": [
{
"introduced": "3.0.0"
},
{
"fixed": "3.0.17"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2018-16191"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2024-04-25T20:40:54Z",
"nvd_published_at": "2019-01-09T23:29:00Z",
"severity": "MODERATE"
},
"details": "Open redirect vulnerability in EC-CUBE (EC-CUBE 3.0.0, EC-CUBE 3.0.1, EC-CUBE 3.0.2, EC-CUBE 3.0.3, EC-CUBE 3.0.4, EC-CUBE 3.0.5, EC-CUBE 3.0.6, EC-CUBE 3.0.7, EC-CUBE 3.0.8, EC-CUBE 3.0.9, EC-CUBE 3.0.10, EC-CUBE 3.0.11, EC-CUBE 3.0.12, EC-CUBE 3.0.12-p1, EC-CUBE 3.0.13, EC-CUBE 3.0.14, EC-CUBE 3.0.15, EC-CUBE 3.0.16) allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via unspecified vectors.",
"id": "GHSA-fcgg-qgxg-2g2x",
"modified": "2024-09-13T19:33:37Z",
"published": "2022-05-14T01:36:14Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-16191"
},
{
"type": "PACKAGE",
"url": "https://github.com/EC-CUBE/ec-cube"
},
{
"type": "WEB",
"url": "https://jvn.jp/en/jp/JVN25359688/index.html"
},
{
"type": "WEB",
"url": "https://www.ec-cube.net/info/weakness/20181113"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/106545"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "EC-CUBE Open redirect vulnerability"
}
GHSA-FF4Q-64JC-GX98
Vulnerability from github – Published: 2024-07-31 15:28 – Updated: 2024-07-31 19:57Impact
It is possible for an attacker to craft malicious Urls that certain functions in IdentityServer will incorrectly treat as local and trusted. If such a Url is returned as a redirect, some browsers will follow it to a third-party, untrusted site.
Note: by itself, this vulnerability does not allow an attacker to obtain user credentials, authorization codes, access tokens, refresh tokens, or identity tokens. An attacker could however exploit this vulnerability as part of a phishing attack designed to steal user credentials.
Affected Methods
- In the
DefaultIdentityServerInteractionService, theGetAuthorizationContextAsyncmethod may return non-null and theIsValidReturnUrlmethod may return true for malicious Urls, indicating incorrectly that they can be safely redirected to.
UI code calling these two methods is the most commonly used code path that will expose the vulnerability. The default UI templates rely on this behavior in the Login, Challenge, Consent, and Account Creation pages. Customized user interface code might also rely on this behavior. The following uncommonly used APIs are also vulnerable:
- The
ServerUrlExtensions.GetIdentityServerRelativeUrl,ReturnUrlParser.ParseAsyncandOidcReturnUrlParser.ParseAsyncmethods may incorrectly return non-null, and theReturnUrlParser.IsValidReturnUrlandOidcReturnUrlParser.IsValidReturnUrlmethods may incorrectly return true for malicious Urls.
Patches
This vulnerability is fixed in the following versions of Duende.IdentityServer: - 7.0.6 - 6.3.10 - 6.2.5 - 6.1.8 - 6.0.5
Duende.IdentityServer 5.1 and earlier and all versions of IdentityServer4 are no longer supported and will not be receiving updates.
Workarounds
If upgrading is not possible, use IUrlHelper.IsLocalUrl from ASP.NET Core 5.0 or later to validate return Urls in user interface code in the IdentityServer host.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 7.0.5"
},
"package": {
"ecosystem": "NuGet",
"name": "Duende.IdentityServer"
},
"ranges": [
{
"events": [
{
"introduced": "7.0.0-preview.1"
},
{
"fixed": "7.0.6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 6.3.9"
},
"package": {
"ecosystem": "NuGet",
"name": "Duende.IdentityServer"
},
"ranges": [
{
"events": [
{
"introduced": "6.3.0-preview.1"
},
{
"fixed": "6.3.10"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 6.2.4"
},
"package": {
"ecosystem": "NuGet",
"name": "Duende.IdentityServer"
},
"ranges": [
{
"events": [
{
"introduced": "6.2.0-preview.1"
},
{
"fixed": "6.2.5"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 6.1.7"
},
"package": {
"ecosystem": "NuGet",
"name": "Duende.IdentityServer"
},
"ranges": [
{
"events": [
{
"introduced": "6.1.0-preview.1"
},
{
"fixed": "6.1.8"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 6.0.4"
},
"package": {
"ecosystem": "NuGet",
"name": "Duende.IdentityServer"
},
"ranges": [
{
"events": [
{
"introduced": "6.0.0-preview.1"
},
{
"fixed": "6.0.5"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "IdentityServer4"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "4.1.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-39694"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2024-07-31T15:28:54Z",
"nvd_published_at": "2024-07-31T16:15:04Z",
"severity": "MODERATE"
},
"details": "### Impact\nIt is possible for an attacker to craft malicious Urls that certain functions in IdentityServer will incorrectly treat as local and trusted. If such a Url is returned as a redirect, some browsers will follow it to a third-party, untrusted site.\n\n_Note: by itself, this vulnerability does **not** allow an attacker to obtain user credentials, authorization codes, access tokens, refresh tokens, or identity tokens. An attacker could however exploit this vulnerability as part of a phishing attack designed to steal user credentials._\n\n### Affected Methods\n- In the `DefaultIdentityServerInteractionService`, the `GetAuthorizationContextAsync` method may return non-null and the `IsValidReturnUrl` method may return true for malicious Urls, indicating incorrectly that they can be safely redirected to.\n\n _UI code calling these two methods is the most commonly used code path that will expose the vulnerability. The default UI templates rely on this behavior in the Login, Challenge, Consent, and Account Creation pages. Customized user interface code might also rely on this behavior. The following uncommonly used APIs are also vulnerable:_\n\n- The `ServerUrlExtensions.GetIdentityServerRelativeUrl`, `ReturnUrlParser.ParseAsync` and `OidcReturnUrlParser.ParseAsync` methods may incorrectly return non-null, and the `ReturnUrlParser.IsValidReturnUrl` and `OidcReturnUrlParser.IsValidReturnUrl` methods may incorrectly return true for malicious Urls.\n\n### Patches\nThis vulnerability is fixed in the following versions of Duende.IdentityServer:\n- 7.0.6\n- 6.3.10\n- 6.2.5\n- 6.1.8\n- 6.0.5\n\nDuende.IdentityServer 5.1 and earlier and all versions of IdentityServer4 are no longer supported and will not be receiving updates. \n\n### Workarounds\n\nIf upgrading is not possible, use `IUrlHelper.IsLocalUrl` from ASP.NET Core 5.0 or later to validate return Urls in user interface code in the IdentityServer host. ",
"id": "GHSA-ff4q-64jc-gx98",
"modified": "2024-07-31T19:57:30Z",
"published": "2024-07-31T15:28:54Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/DuendeSoftware/IdentityServer/security/advisories/GHSA-ff4q-64jc-gx98"
},
{
"type": "WEB",
"url": "https://github.com/IdentityServer/IdentityServer4/security/advisories/GHSA-55p7-v223-x366"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-39694"
},
{
"type": "WEB",
"url": "https://github.com/DuendeSoftware/IdentityServer/commit/269ca2171fe1e901c87f2f0797bbc7c230db87c6"
},
{
"type": "WEB",
"url": "https://github.com/DuendeSoftware/IdentityServer/commit/765116a2d4fb0671b6eba015e698533900c61c8e"
},
{
"type": "WEB",
"url": "https://github.com/DuendeSoftware/IdentityServer/commit/d0d8eab35ad9183b14925496803ed8b36658d0a1"
},
{
"type": "WEB",
"url": "https://github.com/DuendeSoftware/IdentityServer/commit/f04cf0be859b93f43563f8f812eb92206ad94011"
},
{
"type": "WEB",
"url": "https://github.com/DuendeSoftware/IdentityServer/commit/fe817b499933d6ed6141b153492d7335c28b184a"
},
{
"type": "PACKAGE",
"url": "https://github.com/DuendeSoftware/IdentityServer"
}
],
"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"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "IdentityServer Open Redirect vulnerability"
}
GHSA-FF8H-XG3Q-FJ52
Vulnerability from github – Published: 2022-03-31 00:00 – Updated: 2022-04-07 00:00Archer 6.x through 6.9 P2 (6.9.0.2) is affected by an open redirect vulnerability. A remote unprivileged attacker may potentially redirect legitimate users to arbitrary web sites and conduct phishing attacks. The attacker could then steal the victims' credentials and silently authenticate them to the Archer application without the victims realizing an attack occurred.
{
"affected": [],
"aliases": [
"CVE-2022-26950"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-03-30T00:15:00Z",
"severity": "MODERATE"
},
"details": "Archer 6.x through 6.9 P2 (6.9.0.2) is affected by an open redirect vulnerability. A remote unprivileged attacker may potentially redirect legitimate users to arbitrary web sites and conduct phishing attacks. The attacker could then steal the victims\u0027 credentials and silently authenticate them to the Archer application without the victims realizing an attack occurred.",
"id": "GHSA-ff8h-xg3q-fj52",
"modified": "2022-04-07T00:00:29Z",
"published": "2022-03-31T00:00:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-26950"
},
{
"type": "WEB",
"url": "https://www.archerirm.community/t5/general-support-information/tkb-p/information-support"
},
{
"type": "WEB",
"url": "https://www.archerirm.community/t5/security-advisories/archer-an-rsa-business-update-for-multiple-vulnerabilities/ta-p/674497"
}
],
"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-FFJ6-5GWW-48QC
Vulnerability from github – Published: 2022-05-13 01:07 – Updated: 2022-05-13 01:07The OAuth authorization implementation in Pivotal Cloud Foundry (PCF) before 242; UAA 2.x before 2.7.4.7, 3.x before 3.3.0.5, and 3.4.x before 3.4.4; UAA BOSH before 11.5 and 12.x before 12.5; Elastic Runtime before 1.6.40, 1.7.x before 1.7.21, and 1.8.x before 1.8.1; and Ops Manager 1.7.x before 1.7.13 and 1.8.x before 1.8.1 mishandles redirect_uri subdomains, which allows remote attackers to obtain implicit access tokens via a modified subdomain.
{
"affected": [],
"aliases": [
"CVE-2016-6636"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2016-09-30T00:59:00Z",
"severity": "MODERATE"
},
"details": "The OAuth authorization implementation in Pivotal Cloud Foundry (PCF) before 242; UAA 2.x before 2.7.4.7, 3.x before 3.3.0.5, and 3.4.x before 3.4.4; UAA BOSH before 11.5 and 12.x before 12.5; Elastic Runtime before 1.6.40, 1.7.x before 1.7.21, and 1.8.x before 1.8.1; and Ops Manager 1.7.x before 1.7.13 and 1.8.x before 1.8.1 mishandles redirect_uri subdomains, which allows remote attackers to obtain implicit access tokens via a modified subdomain.",
"id": "GHSA-ffj6-5gww-48qc",
"modified": "2022-05-13T01:07:26Z",
"published": "2022-05-13T01:07:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2016-6636"
},
{
"type": "WEB",
"url": "https://pivotal.io/security/cve-2016-6636"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/93246"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-FFPG-GM3H-4P5P
Vulnerability from github – Published: 2025-11-18 18:32 – Updated: 2025-11-19 18:59Host Header Injection vulnerability in Backdrop CMS 1.32.1 allows attackers to manipulate the Host header in password reset requests, leading to redirects to malicious domains and potential session hijacking via cookie injection.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "backdrop/backdrop"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "1.32.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-63828"
],
"database_specific": {
"cwe_ids": [
"CWE-601",
"CWE-644"
],
"github_reviewed": true,
"github_reviewed_at": "2025-11-18T21:56:57Z",
"nvd_published_at": "2025-11-18T18:16:13Z",
"severity": "MODERATE"
},
"details": "Host Header Injection vulnerability in Backdrop CMS 1.32.1 allows attackers to manipulate the Host header in password reset requests, leading to redirects to malicious domains and potential session hijacking via cookie injection.",
"id": "GHSA-ffpg-gm3h-4p5p",
"modified": "2025-11-19T18:59:46Z",
"published": "2025-11-18T18:32:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-63828"
},
{
"type": "PACKAGE",
"url": "https://github.com/backdrop/backdrop"
},
{
"type": "WEB",
"url": "https://github.com/mertdurum06/BackdropCms-1.32.1"
},
{
"type": "WEB",
"url": "https://github.com/mertdurum06/BackdropCms-1.32.1/blob/main/backdropcms_exploit.txt"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:P",
"type": "CVSS_V4"
}
],
"summary": "Backdrop CMS Host Header Injection vulnerability"
}
GHSA-FFV6-5MRV-QXF3
Vulnerability from github – Published: 2022-05-24 17:45 – Updated: 2022-05-24 17:45Tableau Server fails to validate certain URLs that are embedded in emails sent to Tableau Server users.
{
"affected": [],
"aliases": [
"CVE-2021-1629"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-03-26T17:15:00Z",
"severity": "MODERATE"
},
"details": "Tableau Server fails to validate certain URLs that are embedded in emails sent to Tableau Server users.",
"id": "GHSA-ffv6-5mrv-qxf3",
"modified": "2022-05-24T17:45:31Z",
"published": "2022-05-24T17:45:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-1629"
},
{
"type": "WEB",
"url": "https://help.salesforce.com/articleView?id=000357424\u0026type=1\u0026mode=1"
},
{
"type": "WEB",
"url": "http://packetstormsecurity.com/files/162138/Tableau-Server-Open-Redirection.html"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2021/Apr/22"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-FGVW-2V52-JHFV
Vulnerability from github – Published: 2024-09-17 00:31 – Updated: 2024-09-17 00:31An issue has been discovered in GitLab EE affecting all versions starting from 11.1 before 17.1.7, 17.2 before 17.2.5, and 17.3 before 17.3.2. Under certain conditions an open redirect vulnerability could allow for an account takeover by breaking the OAuth flow.
{
"affected": [],
"aliases": [
"CVE-2024-4283"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-09-16T22:15:20Z",
"severity": "MODERATE"
},
"details": "An issue has been discovered in GitLab EE affecting all versions starting from 11.1 before 17.1.7, 17.2 before 17.2.5, and 17.3 before 17.3.2. Under certain conditions an open redirect vulnerability could allow for an account takeover by breaking the OAuth flow.",
"id": "GHSA-fgvw-2v52-jhfv",
"modified": "2024-09-17T00:31:02Z",
"published": "2024-09-17T00:31:02Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-4283"
},
{
"type": "WEB",
"url": "https://hackerone.com/reports/2474286"
},
{
"type": "WEB",
"url": "https://gitlab.com/gitlab-org/gitlab/-/issues/458502"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-FH35-P8PH-P545
Vulnerability from github – Published: 2022-05-14 02:48 – Updated: 2023-08-02 21:02Open redirect vulnerability in SilverStripe CMS & Framework 3.1.13 allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a URL in the returnURL parameter to dev/build.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "silverstripe/cms"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "3.1.13"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Packagist",
"name": "silverstripe/framework"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "3.1.13"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2015-5062"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2023-08-02T21:02:12Z",
"nvd_published_at": "2015-06-24T14:59:00Z",
"severity": "MODERATE"
},
"details": "Open redirect vulnerability in SilverStripe CMS \u0026 Framework 3.1.13 allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a URL in the returnURL parameter to dev/build.",
"id": "GHSA-fh35-p8ph-p545",
"modified": "2023-08-02T21:02:12Z",
"published": "2022-05-14T02:48:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2015-5062"
},
{
"type": "WEB",
"url": "https://web.archive.org/web/20200228091958/http://www.securityfocus.com/bid/75419"
},
{
"type": "WEB",
"url": "https://web.archive.org/web/20201209000421/http://www.securityfocus.com/archive/1/535716/100/0/threaded"
},
{
"type": "WEB",
"url": "http://hyp3rlinx.altervista.org/advisories/AS-SILVERSTRIPE0607.txt"
},
{
"type": "WEB",
"url": "http://packetstormsecurity.com/files/132223/SilverStripe-CMS-3.1.13-XSS-Open-Redirect.html"
}
],
"schema_version": "1.4.0",
"severity": [],
"summary": "Silverstripe CMS Open Redirect"
}
GHSA-FH3H-VG37-CC95
Vulnerability from github – Published: 2026-06-04 14:33 – Updated: 2026-07-18 17:27Impact
When WebOb normalizes the HTTP Location header to include the request hostname, it does so by parsing the URL that the user is to be redirected to with Python's urllib.parse, and joining it to the base URL. urlsplit (called internally by urljoin) however treats a // at the start of a string as a URI without a scheme, and then treats the next part as the hostname. urljoin will then use that hostname from the second part as the hostname replacing the original one from the request.
In a previous advisory https://github.com/Pylons/webob/security/advisories/GHSA-mg3v-6m49-jhp3 an attempt to fix this was made by forcing the replacement of // with /%2f, however this did not take into account that since Python 3.10 urlsplit internally strips ASCII tab, carriage return, and newline characters from the string, so /\t/attacker.com gets turned into //attacker.com and the attacker is able to bypass the changes introduced in that previous advisory, thereby bringing back the problem that was attempted to be fixed.
>>> parse.urlparse("//attacker.com/some/path")
ParseResult(scheme='', netloc='attacker.com', path='/some/path', params='', query='', fragment='')
WebOb uses urljoin to take the request URI and join the redirect location to it, so assuming the request URI is https://example.org/ and the URL to redirect to is /\t/attacker.com/some/path/:
>>> parse.urljoin("https://example.org/", "/\t/attacker.com/some/path/")
'https://attacker.com/some/path/'
Which redirects from example.org where we want the user to stay to attacker.com.
Patches
This issue has been fixed in WebOb 1.8.10.
Workarounds
Any use of the Response class that includes a location can be rewritten to make sure to always pass a full URI that includes the hostname to redirect the user to, or to validate that the redirect target starts with a scheme (e.g. http:// or https://) before assigning to Response.location.
References
- https://github.com/Pylons/webob/security/advisories/GHSA-mg3v-6m49-jhp3
- CVE-2024-42353
Thanks
- Caleb Brown of Google
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 1.8.9"
},
"package": {
"ecosystem": "PyPI",
"name": "webob"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.8.10"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-44889"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-04T14:33:35Z",
"nvd_published_at": "2026-06-22T22:16:46Z",
"severity": "MODERATE"
},
"details": "### Impact\n\nWhen WebOb normalizes the HTTP Location header to include the request hostname, it does so by parsing the URL that the user is to be redirected to with Python\u0027s `urllib.parse`, and joining it to the base URL. `urlsplit` (called internally by `urljoin`) however treats a `//` at the start of a string as a URI without a scheme, and then treats the next part as the hostname. `urljoin` will then use that hostname from the second part as the hostname replacing the original one from the request.\n\nIn a previous advisory https://github.com/Pylons/webob/security/advisories/GHSA-mg3v-6m49-jhp3 an attempt to fix this was made by forcing the replacement of `//` with `/%2f`, however this did not take into account that since Python 3.10 `urlsplit` internally strips ASCII tab, carriage return, and newline characters from the string, so `/\\t/attacker.com` gets turned into `//attacker.com` and the attacker is able to bypass the changes introduced in that previous advisory, thereby bringing back the problem that was attempted to be fixed.\n\n```\n\u003e\u003e\u003e parse.urlparse(\"//attacker.com/some/path\")\nParseResult(scheme=\u0027\u0027, netloc=\u0027attacker.com\u0027, path=\u0027/some/path\u0027, params=\u0027\u0027, query=\u0027\u0027, fragment=\u0027\u0027)\n```\n\nWebOb uses `urljoin` to take the request URI and join the redirect location to it, so assuming the request URI is `https://example.org/` and the URL to redirect to is `/\\t/attacker.com/some/path/`:\n\n```\n\u003e\u003e\u003e parse.urljoin(\"https://example.org/\", \"/\\t/attacker.com/some/path/\")\n\u0027https://attacker.com/some/path/\u0027\n```\n\nWhich redirects from `example.org` where we want the user to stay to `attacker.com`.\n\n### Patches\n\nThis issue has been fixed in WebOb 1.8.10.\n\n### Workarounds\n\nAny use of the `Response` class that includes a `location` can be rewritten to make sure to always pass a full URI that includes the hostname to redirect the user to, or to validate that the redirect target starts with a scheme (e.g. `http://` or `https://`) before assigning to `Response.location`.\n\n### References\n\n- https://github.com/Pylons/webob/security/advisories/GHSA-mg3v-6m49-jhp3\n- CVE-2024-42353\n\n### Thanks\n\n- Caleb Brown of Google",
"id": "GHSA-fh3h-vg37-cc95",
"modified": "2026-07-18T17:27:38Z",
"published": "2026-06-04T14:33:35Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/Pylons/webob/security/advisories/GHSA-fh3h-vg37-cc95"
},
{
"type": "WEB",
"url": "https://github.com/Pylons/webob/security/advisories/GHSA-mg3v-6m49-jhp3"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44889"
},
{
"type": "WEB",
"url": "https://github.com/Pylons/webob/commit/1f681a4f17fc10777ef861e8b43ecb26053bc539"
},
{
"type": "WEB",
"url": "https://github.com/Pylons/webob/commit/2b9fbedafb31180c910cf8526e9ea72b4603d0bc"
},
{
"type": "PACKAGE",
"url": "https://github.com/Pylons/webob"
},
{
"type": "WEB",
"url": "https://github.com/Pylons/webob/releases/tag/1.8.10"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/webob/PYSEC-2026-251.yaml"
}
],
"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"
}
],
"summary": "WebOb: Location header normalization during redirect leads to open redirect - again"
}
GHSA-FH6P-H273-W8FF
Vulnerability from github – Published: 2022-05-01 02:25 – Updated: 2024-02-09 03:32Blackboard Learning and Community Portal System in Academic Suite 6.3.1.424, 6.2.3.23, and other versions before 6 allows remote attackers to redirect users to other URLs and conduct phishing attacks via a modified url parameter to frameset.jsp, which loads the URL into a frame and causes it to appear to be part of a valid page.
{
"affected": [],
"aliases": [
"CVE-2005-4206"
],
"database_specific": {
"cwe_ids": [
"CWE-601"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2005-12-13T11:03:00Z",
"severity": "MODERATE"
},
"details": "Blackboard Learning and Community Portal System in Academic Suite 6.3.1.424, 6.2.3.23, and other versions before 6 allows remote attackers to redirect users to other URLs and conduct phishing attacks via a modified url parameter to frameset.jsp, which loads the URL into a frame and causes it to appear to be part of a valid page.",
"id": "GHSA-fh6p-h273-w8ff",
"modified": "2024-02-09T03:32:52Z",
"published": "2022-05-01T02:25:05Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2005-4206"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/23558"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/17991"
},
{
"type": "WEB",
"url": "http://www.ipomonis.com/advisories/Bb_6.zip"
},
{
"type": "WEB",
"url": "http://www.osvdb.org/21618"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/15814"
}
],
"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"
}
]
}
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.