CVE-2025-50182: Urllib3 Urllib3 Does Not Control Redirects Vulnerability

MODERATE
Advisory Identifier: GHSA-48p4-8xcf-vxj5
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CVSS 5.3
CWE-601
Published
Advisory Summary

CVE-2025-50182 is a MODERATE (CVSS 5.3) urllib3 does not control redirects vulnerability (CWE-601: URL Redirection to Untrusted Site ('Open Redirect')) affecting Urllib3 libraries in the PyPI ecosystem. The issue involves urllib3 does not control redirects in browsers and node.js. Remediation is available by upgrading affected packages to version 2.5.0.

CVE-2025-50182 at a Glance

CVE Identifier CVE-2025-50182
GHSA Identifier GHSA-48p4-8xcf-vxj5
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
Affected Product Urllib3
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2025-50182

To remediate this vulnerability, upgrade all affected Urllib3 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

urllib3 fixed: 2.5.0 
pip install urllib3>=2.5.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show urllib3

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2025-50182, inspect your installed packages using pip:

pip show urllib3

Analyze the terminal output to locate any version of Urllib3 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.5.0), your application is affected.

Note: The pip show urllib3 command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect'), where the web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. In Urllib3, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

urllib3 [supports](https://urllib3.readthedocs.io/en/2.4.0/reference/contrib/emscripten.html) being used in a Pyodide runtime utilizing the [JavaScript Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) or falling back on [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest). This means you can use Python libraries to make HTTP requests from your browser or Node.js. Additionally, urllib3 provides [a mechanism](https://urllib3.readthedocs.io/en/2.4.0/user-guide.html#retrying-requests) to control redirects. However, the `retries` and `redirect` parameters are ignored with Pyodide; the runtime itself determines redirect behavior. ## Affected usages Any code which relies on urllib3 to control the number of redirects for an HTTP request in a Pyodide runtime. ## Impact Redirects are often used to exploit SSRF vulnerabilities. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects may remain vulnerable if a Pyodide runtime redirect mechanism is unsuitable. ## Remediation If you use urllib3 in Node.js, upgrade to a patched version of urllib3. Unfortunately, browsers provide no suitable way which urllib3 can use: `XMLHttpRequest` provides no control over redirects, the Fetch API returns `opaqueredirect` responses lacking data when redirects are controlled manually. Expect default browser behavior for redirects.

CVE-2025-50182 Affected Urllib3 Versions

1 component(s)
Fixed Versions:
2.5.0
Product / Package Ecosystem Affected Versions Fixed Version
urllib3
pypi/urllib3
PyPI
≥ 2.2.0
< 2.5.0
2.5.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/urllib3/urllib3/security/advisories/GHSA-48p4-8xcf-vxj5
NVD — CVE-2025-50182 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-50182
Security Fix Commit FIX COMMIT
https://github.com/urllib3/urllib3/commit/7eb4a2aafe49a279c29b6d1f0ed0f42e9736194f
Urllib3 Source Repository REPOSITORY
https://github.com/urllib3/urllib3
Urllib3 Release RELEASE
https://github.com/urllib3/urllib3/releases/tag/2.5.0

Frequently Asked Questions

What is CVE-2025-50182?
CVE-2025-50182 is a security vulnerability in Urllib3 involving urllib3 does not control redirects in browsers and Node.js under CWE-601: URL Redirection to Untrusted Site ('Open Redirect').
Which Urllib3 versions are affected?
Affected versions include releases prior to 2.5.0 across affected packages: urllib3.
What version fixes CVE-2025-50182?
Upgrading to 2.5.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is urllib3 affected?
Yes, urllib3 is affected in releases prior to 2.5.0. Upgrade your dependency to 2.5.0 or later.
What is the CVSS score of CVE-2025-50182?
CVE-2025-50182 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2025-50182?
CVE-2025-50182 is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect') (The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.).
How can I check PyPI dependencies for CVE-2025-50182?
Run the dependency tree command: 'pip show urllib3'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-48p4-8xcf-vxj5",
  "modified" : "2025-12-22T18:43:35Z",
  "published" : "2025-06-18T17:50:11Z",
  "aliases" : [ "CVE-2025-50182" ],
  "summary" : "urllib3 does not control redirects in browsers and Node.js",
  "details" : "urllib3 [supports](https://urllib3.readthedocs.io/en/2.4.0/reference/contrib/emscripten.html) being used in a Pyodide runtime utilizing the [JavaScript Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) or falling back on [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest). This means you can use Python libraries to make HTTP requests from your browser or Node.js. Additionally, urllib3 provides [a mechanism](https://urllib3.readthedocs.io/en/2.4.0/user-guide.html#retrying-requests) to control redirects.\n\nHowever, the `retries` and `redirect` parameters are ignored with Pyodide; the runtime itself determines redirect behavior.\n\n\n## Affected usages\n\nAny code which relies on urllib3 to control the number of redirects for an HTTP request in a Pyodide runtime.\n\n\n## Impact\n\nRedirects are often used to exploit SSRF vulnerabilities. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects may remain vulnerable if a Pyodide runtime redirect mechanism is unsuitable.\n\n\n## Remediation\n\nIf you use urllib3 in Node.js, upgrade to a patched version of urllib3.\n\nUnfortunately, browsers provide no suitable way which urllib3 can use: `XMLHttpRequest` provides no control over redirects, the Fetch API returns `opaqueredirect` responses lacking data when redirects are controlled manually. Expect default browser behavior for redirects.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "urllib3"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
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      }, {
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      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/urllib3/urllib3/security/advisories/GHSA-48p4-8xcf-vxj5"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-50182"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/urllib3/urllib3/commit/7eb4a2aafe49a279c29b6d1f0ed0f42e9736194f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/urllib3/urllib3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/urllib3/urllib3/releases/tag/2.5.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-601" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-06-18T17:50:11Z",
    "nvd_published_at" : "2025-06-19T02:15:17Z"
  }
}