urllib3 previously wouldn't remove the HTTP request body when an HTTP redirect response using status 303 "See Other" after the request had its method changed from one that could accept a request body (like POST) to GET as is required by HTTP RFCs. Although the behavior of removing the request body is not specified in the section for redirects, it can be inferred by piecing together information from different sections and we have observed the behavior in other major HTTP client implementations like curl and web browsers.
A client SHOULD NOT generate content in a GET request unless it is made directly to an origin server that has previously indicated, in or out of band, that such a request has a purpose and will be adequately supported.
Affected usages
Because the vulnerability requires a previously trusted service to become compromised in order to have an impact on confidentiality we believe the exploitability of this vulnerability is low. Additionally, many users aren't putting sensitive data in HTTP request bodies, if this is the case then this vulnerability isn't exploitable.
Both of the following conditions must be true to be affected by this vulnerability:
If you're using urllib3 and submitting sensitive information in the HTTP request body (such as form data or JSON)
The origin service is compromised and starts redirecting using 303 to a malicious peer or the redirected-to service becomes compromised.
Remediation
You can remediate this vulnerability with any of the following steps:
Upgrade to a patched version of urllib3 (v1.26.18 or v2.0.7)
Disable redirects for services that you aren't expecting to respond with redirects with redirects=False.
Disable automatic redirects with redirects=False and handle 303 redirects manually by stripping the HTTP request body.
Release Notes
urllib3/urllib3 (urllib3)
### [`v1.26.18`](https://togithub.com/urllib3/urllib3/blob/HEAD/CHANGES.rst#12618-2023-10-17)
[Compare Source](https://togithub.com/urllib3/urllib3/compare/1.26.17...1.26.18)
\====================
- Made body stripped from HTTP requests changing the request method to GET after HTTP 303 "See Other" redirect responses.
Configuration
📅 Schedule: Branch creation - "" (UTC), Automerge - At any time (no schedule defined).
🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.
♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.
🔕 Ignore: Close this PR and you won't be reminded about this update again.
[ ] If you want to rebase/retry this PR, check this box
This PR contains the following updates:
==1.26.17->==1.26.18GitHub Vulnerability Alerts
CVE-2023-45803
urllib3 previously wouldn't remove the HTTP request body when an HTTP redirect response using status 303 "See Other" after the request had its method changed from one that could accept a request body (like
POST) toGETas is required by HTTP RFCs. Although the behavior of removing the request body is not specified in the section for redirects, it can be inferred by piecing together information from different sections and we have observed the behavior in other major HTTP client implementations like curl and web browsers.From RFC 9110 Section 9.3.1:
Affected usages
Because the vulnerability requires a previously trusted service to become compromised in order to have an impact on confidentiality we believe the exploitability of this vulnerability is low. Additionally, many users aren't putting sensitive data in HTTP request bodies, if this is the case then this vulnerability isn't exploitable.
Both of the following conditions must be true to be affected by this vulnerability:
Remediation
You can remediate this vulnerability with any of the following steps:
redirects=False.redirects=Falseand handle 303 redirects manually by stripping the HTTP request body.Release Notes
urllib3/urllib3 (urllib3)
### [`v1.26.18`](https://togithub.com/urllib3/urllib3/blob/HEAD/CHANGES.rst#12618-2023-10-17) [Compare Source](https://togithub.com/urllib3/urllib3/compare/1.26.17...1.26.18) \==================== - Made body stripped from HTTP requests changing the request method to GET after HTTP 303 "See Other" redirect responses.Configuration
📅 Schedule: Branch creation - "" (UTC), Automerge - At any time (no schedule defined).
🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.
♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.
🔕 Ignore: Close this PR and you won't be reminded about this update again.
This PR has been generated by Renovate Bot.