CVE-2025-24023 Observable Response Discrepancy in flask-appbuilder
Unauthenticated attackers can enumerate valid usernames by analyzing response timing discrepancies during login attempts in Flask-AppBuilder.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-24023?
CVE-2025-24023 is a low-severity vulnerability in dpgaspar Flask-AppBuilder, published on 3 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Flask-AppBuilder is an application development framework. Prior to 4.5.3, Flask-AppBuilder allows unauthenticated users to enumerate existing usernames by timing the response time from the server when brute forcing requests to login. This vulnerability is fixed in 4.5.3.
Which versions are affected by CVE-2025-24023?
3 open source packages ship an affected version, including flask-appbuilder. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
flask-appbuilder PyPI | All versions | 4.5.3 |
flask-appbuilder PyPI | All versions | 4.5.3 |
flask-appbuilder PyPI | All versions | 4.5.3 |
Products include Dpgaspar Flask-Appbuilder.
How do I fix CVE-2025-24023?
Upgrade flask-appbuilder to 4.5.3 or later.
Is CVE-2025-24023 being exploited?
There is no known exploitation of CVE-2025-24023 in the wild and no public exploit code.
Other vulnerabilities in dpgaspar Flask-AppBuilder
- CVE-2024-25128 Flask-AppBuilder incorrect authentication when using auth type OpenID
- CVE-2021-41265 Improper Authentication in Flask-AppBuilder
- CVE-2023-29005 No Rate Limiting on Login AUTH DB
- CVE-2021-32805 URL Redirection to Untrusted Site ('Open Redirect') in Flask-AppBuilder
- CVE-2025-58065 Flask App Builder has an Authentication Bypass vulnerability when using non AUTH_DB methods
Sources
Also known as CLEANSTART-2026-KC19825, CLEANSTART-2026-LB63084, ECHO-04ff-1109-61d3, GHSA-p8q5-cvwx-wvwp, PYSEC-2025-15.