Python CPython up to 3.14.x xml.dom.minidom appendChild algorithmic complexity

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Python CPython up to 3.14.x. The affected element is the function appendChild of the component xml.dom.minidom. This manipulation causes algorithmic complexity. The identification of this vulnerability is CVE-2025-12084. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Python CPython up to 3.14.x and classified as problematic. Affected by this vulnerability is the function appendChild of the component xml.dom.minidom. The manipulation with an unknown input leads to a algorithmic complexity vulnerability. The CWE definition for the vulnerability is CWE-407. 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. As an impact it is known to affect availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2025-12084 since 10/22/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 277446 (Linux Distros Unpatched Vulnerability : CVE-2025-12084), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.15.0 eliminates this vulnerability. Applying the patch 08d8e18ad81cd45bc4a27d6da478b51ea49486e4 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (277446) and CERT Bund (WID-SEC-2025-2741). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • IBM AIX
  • IBM VIOS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • IBM App Connect Enterprise
  • Open Source Python
  • Microsoft Azure Linux
  • Dell Secure Connect Gateway

Productinfo

Type

Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.3
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Algorithmic complexity
CWE: CWE-407 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 277446
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-12084

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CPython 3.15.0
Patch: 08d8e18ad81cd45bc4a27d6da478b51ea49486e4

Timelineinfo

10/22/2025 CVE reserved
12/03/2025 +42 days Advisory disclosed
12/03/2025 +0 days VulDB entry created
04/24/2026 +142 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 142145
Status: Confirmed

CVE: CVE-2025-12084 (🔒)
GCVE (CVE): GCVE-0-2025-12084
GCVE (VulDB): GCVE-100-334219
CERT Bund: WID-SEC-2025-2741 - cPython: Schwachstelle ermöglicht Denial of Service

Entryinfo

Created: 12/03/2025 23:43
Updated: 04/24/2026 14:05
Changes: 12/03/2025 23:43 (72), 12/04/2025 20:38 (2), 12/17/2025 01:17 (10), 12/24/2025 09:59 (7), 01/02/2026 02:42 (1), 01/06/2026 16:00 (1), 01/07/2026 10:56 (1), 01/07/2026 11:21 (1), 01/26/2026 16:46 (1), 01/28/2026 12:43 (1), 02/06/2026 11:31 (1), 03/19/2026 22:49 (1), 04/24/2026 14:05 (1)
Complete: 🔍
Cache ID: 216::103

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