CVE-2025-66418High· 7.5▾ Twilighturllib3 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 co…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 41.3 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Aug 4.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.7%
Last analysed / modified upstream
— → 7.5
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.
urllib3 >= 1.24, < 2.6.0Upgrade past the affected range:
urllib3 2.6.0Affected packages:
urllib3 >= 1.24, < 2.6.0Patched in:
urllib3 2.6.0Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
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