Vulnerability in Busykoala Fastapi-Opa

CVE-2024-40627

Fastapi OPA is an opensource fastapi middleware which includes auth flow. HTTP `OPTIONS` requests are always allowed by `OpaMiddleware`, even when they lack authentication, and are passed through directly to the application. `OpaMiddleware` allows all HTTP `OPTIONS` requests without evaluating it against any policy. If an application provides different responses to HTTP `OPTIONS` requests based on an entity existing (such as to indicate whether an entity is writable on a system level), an unauthenticated attacker could discover which entities exist within an application. This issue has been addressed in release version 2.0.1. All users are advised to upgrade. There are no known workarounds for this vulnerability.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.006 (44.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2024-40627: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2024-40627?
CVE-2024-40627 is a medium-severity vulnerability in Busykoala Fastapi-Opa, classified under Observable Response Discrepancy. CVSS score: 5.8/10. Published 2024-07-15.
How severe is CVE-2024-40627?
Medium severity. CVSS v3 base score is 5.8 out of 10.