CVE-2025-50181 urllib3 redirects are not disabled when retries are disabled on PoolManager instantiation
Attackers can bypass SSRF mitigations in urllib3 when redirects are disabled via specific PoolManager retry configurations, affecting applications relying on this setting.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-50181?
CVE-2025-50181 is a medium-severity server-side request forgery vulnerability in urllib3, published on 19 Jun 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.
Weakness: CWE-601
Which versions are affected by CVE-2025-50181?
3 open source packages ship an affected version, including urllib3. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
urllib3 PyPI | All versions | 2.5.0 |
urllib3 PyPI | All versions | 2.5.0 |
urllib3 PyPI | All versions | 2.5.0 |
Linux distribution packages (16)
python-urllib3 SUSE:Linux Enterprise Micro 5.1 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Micro 5.2 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Micro 5.3 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Micro 5.4 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Micro 5.5 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Module for Basesystem 15 SP6 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 1.25.10-150300.4.18.1 |
python-urllib3 SUSE:Linux Enterprise Module for Public Cloud 12 | All versions | 1.25.10-3.43.1 |
python-urllib3 SUSE:Linux Enterprise Module for Public Cloud 15 SP4 | All versions | 2.0.7-150400.7.21.1 |
python-urllib3 SUSE:Linux Enterprise Module for Python 3 15 SP6 | All versions | 2.0.7-150400.7.21.1 |
python-urllib3 SUSE:Linux Enterprise Module for Python 3 15 SP7 | All versions | 2.0.7-150400.7.21.1 |
python-urllib3 SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 | All versions | 1.25.10-3.43.1 |
python-urllib3 SUSE:Linux Micro 6.0 | All versions | 2.1.0-3.1 |
python-urllib3 SUSE:Linux Micro 6.1 | All versions | 2.1.0-slfo.1.1_2.1 |
python-urllib3 openSUSE:Leap 15.6 | All versions | 2.0.7-150400.7.21.1 |
python-urllib3_1 openSUSE:Tumbleweed | All versions | 1.26.20-3.1 |
Products include Python Urllib3.
How do I fix CVE-2025-50181?
Upgrade urllib3 to 2.5.0 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2025-50181 being exploited?
There is no known exploitation of CVE-2025-50181 in the wild and no public exploit code.
Other vulnerabilities in urllib3
- CVE-2026-97689 urllib3: HTTPResponse.stream()/read_chunked() buffers an unbounded chunk-size line into memory
- CVE-2026-44432 urllib3: Decompression-bomb safeguards bypassed in parts of the streaming API
- CVE-2026-21441 urllib3 vulnerable to decompression-bomb safeguard bypass when following HTTP redirects (streaming API)
- CVE-2025-66418 urllib3 allows an unbounded number of links in the decompression chain
- CVE-2025-66471 urllib3 Streaming API improperly handles highly compressed data
Sources
Also known as AZL-64170, AZL-64175, AZL-64218, AZL-64244, AZL-77823, BELL-CVE-2025-50181 and 29 more.