GHSA-j2pw-vp55-fqqj
CRITICALFlask-AppBuilder vulnerable to incorrect authentication when using auth type OpenID
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
flask-appbuilderReal-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 Flask-AppBuilder is set to AUTH_TYPE AUTH_OID, allows an attacker to forge an HTTP request, that could deceive the backend into using any requested OpenID service. This vulnerability could grant an attacker unauthorised privilege access if a custom OpenID service is deployed by the attacker and accessible by the backend.
This vulnerability is only exploitable when the application is using the old (deprecated 10 years ago) OpenID 2.0 authorization protocol (which is very different from the popular OIDC - Open ID Connect - popular protocol used today). Currently, this protocol is regarded as legacy, with significantly reduced usage and not supported for several years by major authorization providers.
Patches
Upgrade to Flask-AppBuilder 4.3.11
Workarounds
If upgrade is not possible add the following to your config:
from flask import flash, redirect
from flask_appbuilder import expose
from flask_appbuilder.security.sqla.manager import SecurityManager
from flask_appbuilder.security.views import AuthOIDView
from flask_appbuilder.security.forms import LoginForm_oid
basedir = os.path.abspath(os.path.dirname(__file__))
class FixedOIDView(AuthOIDView):
@expose("/login/", methods=["GET", "POST"])
def login(self, flag=True):
form = LoginForm_oid()
if form.validate_on_submit():
identity_url = None
for provider in self.appbuilder.sm.openid_providers:
if provider.get("url") == form.openid.data:
identity_url = form.openid.data
if identity_url is None:
flash(self.invalid_login_message, "warning")
return redirect(self.appbuilder.get_url_for_login)
return super().login(flag=flag)
class FixedSecurityManager(SecurityManager):
authoidview = FixedOIDView
FAB_SECURITY_MANAGER_CLASS = "config.FixedSecurityManager"
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | flask-appbuilder | all versions | 4.3.11 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for flask-appbuilder. 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-appbuilder to 4.3.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-j2pw-vp55-fqqj 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-j2pw-vp55-fqqj 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-j2pw-vp55-fqqj. 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-j2pw-vp55-fqqj in your dependencies?
O3 detects GHSA-j2pw-vp55-fqqj across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.