CVE-2024-37891 – urllib3

Package

Manager: pip
Name: urllib3
Vulnerable Version: >=0 <1.26.19 || >=2.0.0 <2.2.2

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:H/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00142 pctl0.34976

Details

urllib3's Proxy-Authorization request header isn't stripped during cross-origin redirects When using urllib3's proxy support with `ProxyManager`, the `Proxy-Authorization` header is only sent to the configured proxy, as expected. However, when sending HTTP requests *without* using urllib3's proxy support, it's possible to accidentally configure the `Proxy-Authorization` header even though it won't have any effect as the request is not using a forwarding proxy or a tunneling proxy. In those cases, urllib3 doesn't treat the `Proxy-Authorization` HTTP header as one carrying authentication material and thus doesn't strip the header on cross-origin redirects. Because this is a highly unlikely scenario, we believe the severity of this vulnerability is low for almost all users. Out of an abundance of caution urllib3 will automatically strip the `Proxy-Authorization` header during cross-origin redirects to avoid the small chance that users are doing this on accident. Users should use urllib3's proxy support or disable automatic redirects to achieve safe processing of the `Proxy-Authorization` header, but we still decided to strip the header by default in order to further protect users who aren't using the correct approach. ## Affected usages We believe the number of usages affected by this advisory is low. It requires all of the following to be true to be exploited: * Setting the `Proxy-Authorization` header without using urllib3's built-in proxy support. * Not disabling HTTP redirects. * Either not using an HTTPS origin server or for the proxy or target origin to redirect to a malicious origin. ## Remediation * Using the `Proxy-Authorization` header with urllib3's `ProxyManager`. * Disabling HTTP redirects using `redirects=False` when sending requests. * Not using the `Proxy-Authorization` header.

Metadata

Created: 2024-06-17T21:37:20Z
Modified: 2024-12-18T22:20:24Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/06/GHSA-34jh-p97f-mpxf/GHSA-34jh-p97f-mpxf.json
CWE IDs: ["CWE-669"]
Alternative ID: GHSA-34jh-p97f-mpxf
Finding: F017
Auto approve: 1