CVE-2021-37705

Improper Authorization and Origin Validation Error in OneFuzz

Description

OneFuzz is an open source self-hosted Fuzzing-As-A-Service platform. Starting with OneFuzz 2.12.0 or greater, an incomplete authorization check allows an authenticated user from any Azure Active Directory tenant to make authorized API calls to a vulnerable OneFuzz instance. To be vulnerable, a OneFuzz deployment must be both version 2.12.0 or greater and deployed with the non-default --multi_tenant_domain option. This can result in read/write access to private data such as software vulnerability and crash information, security testing tools and proprietary code and symbols. Via authorized API calls, this also enables tampering with existing data and unauthorized code execution on Azure compute resources. This issue is resolved starting in release 2.31.0, via the addition of application-level check of the bearer token's `issuer` against an administrator-configured allowlist. As a workaround users can restrict access to the tenant of a deployed OneFuzz instance < 2.31.0 by redeploying in the default configuration, which omits the `--multi_tenant_domain` option.

Categories

10.0
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.73% Top 30%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: microsoft onefuzz
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-37705?
CVE-2021-37705 has been scored as a critical severity vulnerability.
How to fix CVE-2021-37705?
To fix CVE-2021-37705, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-37705 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-37705 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37705?
CVE-2021-37705 affects microsoft onefuzz.
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