Python CPython up to 3.14.x API webbrowser.open input validation

CVSS Meta Temp Score
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CTI Interest Score
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2.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Python CPython up to 3.14.x and classified as problematic. This affects the function webbrowser.open of the component API. Executing a manipulation can lead to an unknown weakness. This vulnerability is registered as CVE-2026-4519. The attack needs to be launched locally. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Python CPython up to 3.14.x. This vulnerability affects the function webbrowser.open of the component API. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect integrity. CVE summarizes:

The webbrowser.open() API would accept leading dashes in the URL which could be handled as command line options for certain web browsers. New behavior rejects leading dashes. Users are recommended to sanitize URLs prior to passing to webbrowser.open().

The advisory is available at github.com. This vulnerability was named CVE-2026-4519 since 03/20/2026. The exploitation appears to be difficult. Local access is required to approach this attack. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 303242 (Linux Distros Unpatched Vulnerability : CVE-2026-4519), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.15.0 eliminates this vulnerability. Applying a patch 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 (303242), EUVD (EUVD-2026-13712) and CERT Bund (WID-SEC-2026-0824). 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
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • IBM App Connect Enterprise
  • Open Source Python
  • IBM QRadar SIEM

Productinfo

Type

Vendor

Name

Version

License

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: 2.9
VulDB Meta Temp Score: 2.8

VulDB Base Score: 2.5
VulDB Temp Score: 2.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 3.3
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 303242
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-4519

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CPython 3.15.0
Patch: github.com

Timelineinfo

03/20/2026 Advisory disclosed
03/20/2026 +0 days CVE reserved
03/20/2026 +0 days VulDB entry created
07/01/2026 +103 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 143930
Status: Confirmed

CVE: CVE-2026-4519 (🔒)
GCVE (CVE): GCVE-0-2026-4519
GCVE (VulDB): GCVE-100-352090
EUVD: 🔒
CERT Bund: WID-SEC-2026-0824 - Python: Schwachstelle ermöglicht Codeausführung

Entryinfo

Created: 03/20/2026 17:27
Updated: 07/01/2026 20:29
Changes: 03/20/2026 17:27 (69), 03/20/2026 17:39 (1), 03/22/2026 18:50 (2), 03/23/2026 14:35 (7), 03/26/2026 20:37 (8), 03/28/2026 04:46 (1), 03/31/2026 18:54 (1), 04/24/2026 23:20 (1), 06/24/2026 01:00 (1), 07/01/2026 20:29 (11)
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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