Flask Cors
CVE-2024-6839
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V5 - File Handling Path traversal prevention
|
| Impact | CVSS score of 5.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. EPSS exploitation probability: 0.29%. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAIv1 – Mar 28, 2026
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in pypi
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified under CWE-41. corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors. Affected products include: Flask-Cors Project Flask-Cors. Version information: version 4.0.1.
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Primary rating from NVD.
CVSS VectorNVD
Lifecycle Timeline
3DescriptionCVE.org
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
Executive ViewAI
CVE-2024-6839 presents moderate security risk rated CVSS 5.3. Exploitation could compromise the security of affected deployments. Proof-of-concept code is publicly available. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)CVE.org
More in Flask Cors
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A vulnerability in corydolphin/flask-cors version 4.0.1 allows the `Access-Control-Allow-Private-Network` CORS header to
corydolphin/flask-cors is vulnerable to log injection when the log level is set to debug. Rated medium severity (CVSS 5.
An issue was discovered in Flask-CORS (aka CORS Middleware for Flask) before 3.0.9. Rated high severity (CVSS 7.5), this
A vulnerability in corydolphin/flask-cors version 4.0.1 allows for inconsistent CORS matching due to the handling of the
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB