Python XML DOM minidom quadratic appendChild CVE-2025-12084
CVE-2025-12084 Published on December 3, 2025
Quadratic complexity in node ID cache clearing
When building nested elements using xml.dom.minidom methods such as appendChild() that have a dependency on _clear_id_cache() the algorithm is quadratic. Availability can be impacted when building excessively nested documents.
Weakness Type
Inefficient Algorithmic Complexity
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
Products Associated with CVE-2025-12084
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Affected Versions
Python Software Foundation CPython:- Before 3.10.20 is affected.
- Version 3.11.0 and below 3.11.15 is affected.
- Version 3.12.0 and below 3.12.13 is affected.
- Version 3.13.0 and below 3.13.11 is affected.
- Version 3.14.0 and below 3.14.2 is affected.
- Version 3.15.0a1 and below 3.15.0a3 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.