CVE-2022-36085: open-policy-agent opa Improper Input Validation

Vulnerability summary

CVE-2022-36085 is a critical (CVSS 9.8) Improper Input Validation vulnerability in open-policy-agent opa. EPSS estimates a 1.59% chance of exploitation in the next 30 days, higher than 75.3% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 08-09-2022
   PublishedVulnerability first disclosed.
2. 22-04-2025
   Last modifiedVulnerability information updated.

Description

Open Policy Agent (OPA) is an open source, general-purpose policy engine. The Rego compiler provides a (deprecated) `WithUnsafeBuiltins` function, which allows users to provide a set of built-in functions that should be deemed unsafe — and as such rejected — by the compiler if encountered in the policy compilation stage. A bypass of this protection has been found, where the use of the `with` keyword to mock such a built-in function (a feature introduced in OPA v0.40.0), isn’t taken into account by `WithUnsafeBuiltins`. Multiple conditions need to be met in order to create an adverse effect. Version 0.43.1 contains a patch for this issue. As a workaround, avoid using the `WithUnsafeBuiltins` function and use the `capabilities` feature instead.

• CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
• CWE-693Protection Mechanism FailureThe product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product.