CVE-2025-66418
Last modified
CVE-2025-66418 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.24 and prior to 2.6.0, the number of links in the decompression chain was unbounded allowing a malicious server to insert a virtually unlimited number of compression steps leading to high CPU usage and massive memory allocation for the decompressed data. EPSS estimates a 0.68% chance of exploitation in the next 30 days.
Description
urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.24 and prior to 2.6.0, the number of links in the decompression chain was unbounded allowing a malicious server to insert a virtually unlimited number of compression steps leading to high CPU usage and massive memory allocation for the decompressed data. This vulnerability is fixed in 2.6.0.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Python | Urllib3 | >= 1.24, < 2.6.0 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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