GHSA-fxq4-r6mr-9x64
GHSA-fxq4-r6mr-9x64 is a security vulnerability in flask-security-too. O3 Security confirms whether GHSA-fxq4-r6mr-9x64 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
CSRF Vuln can expose user's QRcode
Real-World Exposure
flask-security-tooReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact
When a user is setting up two-factor authentication using an authenticator app, a QRcode is generated and made available via a GET request to /tf-qrcode. Since GETs do not have any CSRF protection, it is possible a malicious 3rd party could access the QRcode and therefore gain access to two-factor authentication codes. Note that the /tf-qrcode endpoint is ONLY accessible while the user is initially setting up their device. Once setup is complete, there is no vulnerability.
Patches
This is fixed in the upcoming 4.0.0 release.
Workarounds
You can provide your own URL for fetching the QRcode by defining SECURITY_TWO_FACTOR_QRCODE_URL and providing your own implementation (that presumably required a POST with CSRF protection). This would require changing the two-factor setup template as well.
References
None.
For more information
If you have any questions or comments about this advisory:
- Read this pull request: #423
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | flask-security-too | ≥ 3.2.0&&< 3.4.5 | 3.4.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for flask-security-too. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update flask-security-too to 3.4.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fxq4-r6mr-9x64 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-fxq4-r6mr-9x64 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-fxq4-r6mr-9x64. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-fxq4-r6mr-9x64 in your dependencies?
O3 detects GHSA-fxq4-r6mr-9x64 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.