CVE-2021-3737
HighCVSS 7.5Exploitation Probability (EPSS)
Very high risk96th percentile - higher than 96% of all known CVEs
Summary
A flaw in Python's HTTP client code, when improperly handling an HTTP response, may cause the client script to enter an infinite loop, consuming CPU time. The highest threat is to system availability.
Risk Assessment
A remote attacker controlling an HTTP server can cause the client (e.g., a script) to hang in an infinite loop, potentially exhausting CPU resources and causing denial of service for applications.
Recommendation
Update Python to a patched version. Ensure that HTTP client code has timeouts and handles response errors safely.
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- CVE-2021-3177Critical
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Original NVD description (English source)
A flaw was found in python. An improperly handled HTTP response in the HTTP client code of python may allow a remote attacker, who controls the HTTP server, to make the client script enter an infinite loop, consuming CPU time. The highest threat from this vulnerability is to system availability.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS