Medium severity · published Dec 3, 2025
CVE-2025-12084
When building nested elements using xml.dom.minidom methods such as appendChild() that have a dependency on _clear_id_cache() the algorithm is quadratic
5.3
CVSS
0.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
Python · Python
before 3.13.11; 3.14.0 before 3.14.2; 3.15.0; 3.15.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-12084
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-12084
Patch
https://github.com/python/cpython/commit/027f21e417b26eed4505ac2db101a4352b7c51a0
Patch
https://github.com/python/cpython/commit/08d8e18ad81cd45bc4a27d6da478b51ea49486e4
github.com
https://github.com/python/cpython/commit/27648a1818749ef44c420afe6173af6868715437
github.com
https://github.com/python/cpython/commit/41f468786762348960486c166833a218a0a436af
github.com
https://github.com/python/cpython/commit/57937a8e5e293f0dcba5115f7b7a11b1e0c9a273
github.com
https://github.com/python/cpython/commit/8d2d7bb2e754f8649a68ce4116271a4932f76907
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