CVE-2020-26116
HighCVSS 7.2Exploitation Probability (EPSS)
Very high risk93th percentile - higher than 93% of all known CVEs
Summary
http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attacker controls the HTTP request method, e.g., by inserting CR and LF control characters in the first argument of HTTPConnection.request.
Risk Assessment
May lead to HTTP header injection or response splitting (HTTP request smuggling), potentially bypassing security controls.
Recommendation
Upgrade Python to version 3.5.10, 3.6.12, 3.7.9, 3.8.5, or later, which fix this vulnerability.
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Original NVD description (English source)
http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of HTTPConnection.request.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS