Description
A vulnerability in corydolphin/flask-cors version 4.0.1 allows the `Access-Control-Allow-Private-Network` CORS header to be set to true by default. This behavior can expose private network resources to unauthorized external access, leading to significant security risks such as data breaches, unauthorized access to sensitive information, and potential network intrusions.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| corydolphin | corydolphin/flask-cors | unspecified – < 5.0.0 | 5.0.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | python-flask-cors | 5.0.0-1 | — |
| Debian 13 | python-flask-cors | 5.0.0-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | python-flask-cors | 3.0.9-2ubuntu0.1 | USN-7612-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | python-flask-cors | 4.0.0-1ubuntu0.1~esm1 | USN-7612-1 |
| Ubuntu Pro 20.04 LTS | python-flask-cors | 3.0.8-2ubuntu0.1+esm1 | USN-7612-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | kubeflow-jupyter-web-app +1 | 1.9.1-r0 | — |
| Wolfi rolling | py3-flask-cors +5 | 4.0.2-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | flask-cors | < 4.0.2 | 4.0.2 | GHSA-hxwh-jpp2-84pm |
Advisories 1
- USN-7612-1 python-flask-cors vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026