Python CPython up to 3.14.x HTTP Response denial of service

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Python CPython up to 3.14.x. This impacts an unknown function of the component HTTP Response Handler. Such manipulation leads to denial of service. This vulnerability is traded as CVE-2025-13836. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Python CPython up to 3.14.x and classified as problematic. Affected by this issue is an unknown function of the component HTTP Response Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

When reading an HTTP response from a server, if no read amount is specified, the default behavior will be to use Content-Length. This allows a malicious server to cause the client to read large amounts of data into memory, potentially causing OOM or other DoS.

The advisory is available at github.com. This vulnerability is handled as CVE-2025-13836 since 12/01/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 277037 (Linux Distros Unpatched Vulnerability : CVE-2025-13836), 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 4ce27904b597c77d74dd93f2c912676021a99155 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 (277037) and CERT Bund (WID-SEC-2025-2706). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • 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

Productinfo

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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: 6.4
VulDB Meta Temp Score: 6.3

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

NVD Base Score: 7.5
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: 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: 277037
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-13836

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CPython 3.15.0
Patch: 4ce27904b597c77d74dd93f2c912676021a99155

Timelineinfo

12/01/2025 Advisory disclosed
12/01/2025 +0 days CVE reserved
12/01/2025 +0 days VulDB entry created
03/19/2026 +108 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 119451
Status: Confirmed

CVE: CVE-2025-13836 (🔒)
GCVE (CVE): GCVE-0-2025-13836
GCVE (VulDB): GCVE-100-333914
CERT Bund: WID-SEC-2025-2706 - Python: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 12/01/2025 23:25
Updated: 03/19/2026 22:49
Changes: 12/01/2025 23:25 (71), 12/03/2025 10:00 (2), 12/24/2025 09:59 (7), 12/30/2025 18:59 (11), 01/02/2026 02:42 (1), 01/06/2026 10:19 (1), 01/12/2026 13:43 (1), 01/17/2026 17:26 (1), 01/26/2026 16:46 (1), 01/28/2026 18:21 (1), 02/10/2026 21:41 (4), 03/19/2026 22:49 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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