CVE-2020-8492
MediumCVSS 6.5Exploitation Probability (EPSS)
Very high risk94th percentile - higher than 94% of all known CVEs
Summary
Python 2.7 through 2.7.17, 3.5 through 3.5.9, 3.6 through 3.6.10, 3.7 through 3.7.6, and 3.8 through 3.8.1 allows an HTTP server to conduct Regular Expression Denial of Service (ReDoS) attacks against a client because of urllib.request.AbstractBasicAuthHandler catastrophic backtracking.
Risk Assessment
A malicious HTTP server may cause excessive resource consumption on the client side, leading to denial of service. The risk affects applications using urllib.request.AbstractBasicAuthHandler.
Recommendation
Upgrade Python to a patched version or avoid using urllib.request.AbstractBasicAuthHandler when connecting to untrusted servers.
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- CVE-2022-42919High
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.
- CVE-2023-27043Medium
The email module in Python through 3.11.3 incorrectly parses email addresses containing special characters. The wrong portion of an RFC2822 header is identified as the value of the addr-spec.
- CVE-2020-10735High
A flaw was found in Python. In algorithms with quadratic time complexity using non-binary bases, when using int("text"), a system could take 50ms to parse an int string with 100,000 digits and 5s for 1,000,000 digits (float, decimal, int.from_bytes(), and int() for binary bases 2, 4, 8, 16, and 32 are not affected). The highest threat from this vulnerability is to system availability.
- CVE-2019-20907High
In Lib/tarfile.py in Python through 3.8.3, an attacker is able to craft a TAR archive leading to an infinite loop when opened by tarfile.open, because _proc_pax lacks header validation.
- CVE-2019-5010High
Vulnerability in the X509 certificate parser of Python 2.7.11 and 3.6.6 allows denial of service via a specially crafted X509 certificate causing a NULL pointer dereference.
- CVE-2019-16056High
An issue was discovered in Python through 2.7.16, 3.x through 3.5.7, 3.6.x through 3.6.9, and 3.7.x through 3.7.4. The email module wrongly parses email addresses that contain multiple @ characters. An application that uses the email module and implements some kind of checks on the From/To headers of a message could be tricked into accepting an email address that should be denied. An attack may be the same as in CVE-2019-11340; however, this CVE applies to Python more generally.
Original NVD description (English source)
Python 2.7 through 2.7.17, 3.5 through 3.5.9, 3.6 through 3.6.10, 3.7 through 3.7.6, and 3.8 through 3.8.1 allows an HTTP server to conduct Regular Expression Denial of Service (ReDoS) attacks against a client because of urllib.request.AbstractBasicAuthHandler catastrophic backtracking.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

