CVE-2024-25128: Flask-AppBuilder vulnerable to incorrect authentication when using auth type OpenID

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.9%, percentile 58: FIRST’s model estimates a 0.9% chance of exploitation activity in the next 30 days, higher than 58% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes Flask-AppBuilder (PyPI) < 4.3.11, fixed in 4.3.11. Check your lockfile, including transitive dependencies.

What it is

Flask-AppBuilder is an application development framework, built on top of Flask. When Flask-AppBuilder is set to AUTHTYPE AUTHOID, it 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 OpenID 2.0 authorization protocol. Upgrade to Flask-AppBuilder 4.3.11 to fix the vulnerability.

From the GitHub advisory

Impact When Flask-AppBuilder is set to AUTHTYPE AUTHOID, 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:

Weakness type: CWE-287.

Product: Flask-AppBuilder (PyPI) · Assigned by: GitHub_M · Published: 2024-02-28

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.86% probability of exploitation activity in the next 30 days; percentile 58.

Timeline

• 2024-02-28 — CVE record published by GitHub_M
• 2024-02-28 — GitHub-reviewed advisory GHSA-j2pw-vp55-fqqj published (critical)
• 2024-08-26 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-j2pw-vp55-fqqj github.com
2. CVE.org record CVE-2024-25128 cve.org
3. NVD entry CVE-2024-25128 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com

Critical PyPI advisories · Today’s Security Digest