CVE-2021-41125

Scrapy HTTP authentication credentials potentially leaked to target websites

Workarounds

If you cannot upgrade, set your HTTP authentication credentials on a per-request basis, using for example the w3lib.http.basic_auth_header function to convert your credentials into a value that you can assign to the Authorization header of your request, instead of defining your credentials globally using HttpAuthMiddleware.

For more information

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If you use HttpAuthMiddleware (i.e. the http_user and http_pass spider attributes) for HTTP authentication, all requests will expose your credentials to the request target.

This includes requests generated by Scrapy components, such as robots.txt requests sent by Scrapy when the ROBOTSTXT_OBEY setting is set to True, or as requests reached through redirects.

CVE-2021-41125 has a CVSS score of 5.7 (Medium). The vector is network-reachable, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.8.1, 2.5.1); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

Upgrade to Scrapy 2.5.1 and use the new http_auth_domain spider attribute to control which domains are allowed to receive the configured HTTP authentication credentials.

If you are using Scrapy 1.8 or a lower version, and upgrading to Scrapy 2.5.1 is not an option, you may upgrade to Scrapy 1.8.1 instead.

1. What is CVE-2021-41125? CVE-2021-41125 is a medium-severity security vulnerability in Scrapy (pip), affecting versions < 1.8.1. It is fixed in 1.8.1, 2.5.1.
2. How severe is CVE-2021-41125? CVE-2021-41125 has a CVSS score of 5.7 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of Scrapy are affected by CVE-2021-41125? Scrapy (pip) versions < 1.8.1 is affected.
4. Is there a fix for CVE-2021-41125? Yes. CVE-2021-41125 is fixed in 1.8.1, 2.5.1. Upgrade to this version or later.
5. Is CVE-2021-41125 exploitable, and should I be worried? Whether CVE-2021-41125 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2021-41125 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2021-41125?
   • Upgrade Scrapy to 1.8.1 or later
   • Upgrade Scrapy to 2.5.1 or later

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