CVE-2026-4519

Python versions before 3.3.4 RC1 allow remote attackers to cause a denial of service via a file size value larger than the size of the zip file in functions related to reading and extracting zip files.

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.

The email module in Python, specifically the BytesGenerator class, improperly quotes newlines in email headers during serialization, allowing header injection. This only affects usage of LiteralHeader that does not respect email folding.

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.

A vulnerability in the urllib.parse component of Python before version 3.11.4 allows attackers to bypass blocklisting methods by supplying a URL that starts with blank characters.

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.

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.

A flaw in Python's urllib.parse module, where the urlparse method does not sanitize input and allows characters like '\r' and '\n' in the URL path, enabling an attacker to craft a URL that leads to injection attacks. Affected versions are earlier than 3.10.0b1, 3.9.5, 3.8.11, 3.7.11, and 3.6.14.

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.

The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server.