Denial-of-Service Vulnerability in HTML Parser of Python Software Foundation

CVE-2025-6069

What is CVE-2025-6069?

The HTML parser component of the Python Software Foundation is vulnerable to a denial-of-service attack due to its inefficient handling of certain malformed inputs. When processing these inputs, the parser can experience a worst-case quadratic complexity, leading to significant delays and potential service disruption. This vulnerability can be exploited by an attacker who creates specially crafted input, which causes the parser to consume an excessive amount of CPU resources. Users are encouraged to implement the recommended patches and monitor their systems to mitigate potential threats.

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