CVE-2020-15523
HighCVSS 7.8Exploitation Probability (EPSS)
Elevated risk59th percentile - higher than 59% of all known CVEs
Summary
In Python 3.6 through 3.6.10, 3.7 through 3.7.8, 3.8 through 3.8.4rc1, and 3.9 through 3.9.0b4 on Windows, a Trojan horse python3.dll might be used when CPython is embedded in a native application. This occurs because python3X.dll may use an invalid search path for python3.dll loading (after Py_SetPath has been used). This issue cannot occur when using python.exe from a standard (non-embedded) Python installation on Windows.
Risk Assessment
An attacker could replace python3.dll and achieve code execution in the context of the application embedding Python. This only affects applications embedding CPython, not standard Python installations.
Recommendation
Update Python to a version containing the fix (newer than 3.6.10, 3.7.8, 3.8.4rc1, or 3.9.0b4) or secure DLL search directories against unauthorized write access.
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A vulnerability in Python 3.9.x before 3.9.16 and 3.10.x before 3.10.9 on Linux allows local privilege escalation in a non-default configuration. The multiprocessing library with the forkserver start method permits pickle deserialization from any user on the same local network of the machine.
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In Python before 3.9.5, the ipaddress library mishandles leading zero characters in the octets of an IP address string. This (in some situations) allows attackers to bypass access control that is based on IP addresses.
- CVE-2020-27619Critical
In Python 3 through 3.9.0, the Lib/test/multibytecodec_support.py CJK codec tests call eval() on content retrieved via HTTP. This may lead to arbitrary code execution if the content is crafted.
- CVE-2020-26116High
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.
Original NVD description (English source)
In Python 3.6 through 3.6.10, 3.7 through 3.7.8, 3.8 through 3.8.4rc1, and 3.9 through 3.9.0b4 on Windows, a Trojan horse python3.dll might be used in cases where CPython is embedded in a native application. This occurs because python3X.dll may use an invalid search path for python3.dll loading (after Py_SetPath has been used). NOTE: this issue CANNOT occur when using python.exe from a standard (non-embedded) Python installation on Windows.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

