The Long-Term Support Security Release for urllib3.
This ecosystem backports critical security fixes to legacy Python environments (3.7 & 3.8) that official maintainers have dropped.
This release secures 941M+ downloads against the following vulnerabilities:
| Vulnerability | Severity | Impact | Py3.7 | Py3.8 |
|---|---|---|---|---|
| CVE-2025-66471 | 🔴 HIGH | Compression Bomb DoS | 🛡️ Fixed | 🛡️ Fixed |
| CVE-2025-66418 | 🔴 HIGH | Unbounded Links DoS | 🛡️ Fixed | 🛡️ Fixed |
| CVE-2025-50182 | 🟡 MOD | Node.js Redirect Bypass | N/A | 🛡️ Fixed |
| CVE-2025-50181 | 🟡 MOD | Redirect Retry Bypass | 🛡️ Fixed | 🛡️ Fixed |
| CVE-2024-37891 | 🟡 MOD | Proxy-Auth Header Leak | 🛡️ Fixed | N/A |
Standard Installation:
pip install urllib3-ltsThis meta-package automatically detects your Python version and installs the correct secured backport.
Maintained by 1minds3t.
Manage your environment:
pip install omnipkg
omnipkg reset -yWe are building a runtime enforcer that allows configurable WARN or BLOCK policies for unpatched vulnerabilities. Stay tuned.
Before installing urllib3-lts, uninstall any existing urllib3:
pip uninstall urllib3 -y
pip install urllib3-ltsThis ensures you get the security patches. If you install urllib3-lts without removing urllib3 first, other packages may reinstall the vulnerable version.
urllib3-lts-py37==2025.66471.3 ; python_version<'3.8'
urllib3-lts-py38==2025.66471.2 ; python_version>='3.8' and python_version<'3.9'