CVE-2025-66471
- ULN >
- Oracle Linux CVE repository >
- CVE-2025-66471
CVE Details
| Release Date: | 2025-12-05 | |
| Impact: | Important | What is this? |
Description
urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.0 and prior to 2.6.0, the Streaming API improperly handles highly compressed data. urllib3's streaming API is designed for the efficient handling of large HTTP responses by reading the content in chunks, rather than loading the entire response body into memory at once. When streaming a compressed response, urllib3 can perform decoding or decompression based on the HTTP Content-Encoding header (e.g., gzip, deflate, br, or zstd). The library must read compressed data from the network and decompress it until the requested chunk size is met. Any resulting decompressed data that exceeds the requested amount is held in an internal buffer for the next read operation. The decompression logic could cause urllib3 to fully decode a small amount of highly compressed data in a single operation. This can result in excessive resource consumption (high CPU usage and massive memory allocation for the decompressed data.
See more information about CVE-2025-66471 from MITRE CVE dictionary and NIST NVD
NOTE: The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 metrics
| Base Score: | 4.8 |
| Vector String: | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H |
| Version: | 3.1 |
| Attack Vector: | Network |
| Attack Complexity: | High |
| Privileges Required: | Low |
| User Interaction: | Required |
| Scope: | Unchanged |
| Confidentiality Impact: | None |
| Integrity Impact: | None |
| Availability Impact: | High |
Errata information
| Platform | Errata | Release Date |
| Oracle Linux version 10 (python-urllib3) | ELSA-2026-1086 | 2026-01-26 |
| Oracle Linux version 8 (fence-agents) | ELSA-2026-1240 | 2026-01-27 |
| Oracle Linux version 8 (python-urllib3) | ELSA-2026-1254 | 2026-01-26 |
| Oracle Linux version 8 (python3.11-urllib3) | ELSA-2026-1224 | 2026-01-26 |
| Oracle Linux version 8 (python3.12-urllib3) | ELSA-2026-1226 | 2026-01-26 |
| Oracle Linux version 8 (resource-agents) | ELSA-2026-1241 | 2026-01-26 |
| Oracle Linux version 9 (fence-agents) | ELSA-2026-1239 | 2026-01-27 |
| Oracle Linux version 9 (python-urllib3) | ELSA-2026-1087 | 2026-01-26 |
| Oracle Linux version 9 (python3.11-urllib3) | ELSA-2026-1089 | 2026-01-26 |
| Oracle Linux version 9 (python3.12-urllib3) | ELSA-2026-1088 | 2026-01-26 |
This page is generated automatically and has not been checked for errors or omissions. For clarification or corrections:
- Oracle customers - enter a support request
- Vulnerability scanning tools vendors and project maintainers - follow the standard ISV process
