CVE-2022-23628 Array literal misordering in github.com/open-policy-agent/opa

What is CVE-2022-23628?

CVE-2022-23628 is a medium-severity vulnerability in open-policy-agent opa, published on 9 Feb 2022. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

OPA is an open source, general-purpose policy engine. Under certain conditions, pretty-printing an abstract syntax tree (AST) that contains synthetic nodes could change the logic of some statements by reordering array literals. Example of policies impacted are those that parse and compare web paths. **All of these** three conditions have to be met to create an adverse effect: 1. An AST of Rego had to be **created programmatically** such that it ends up containing terms without a location (such as wildcard variables). 2. The AST had to be **pretty-printed** using the `github.com/open-policy-agent/opa/format` package. 3. The result of the pretty-printing had to be **parsed and evaluated again** via an OPA instance using the bundles, or the Golang packages. If any of these three conditions are not met, you are not affected. Notably, all three would be true if using **optimized bundles**, i.e. bundles created with `opa build -O=1` or higher. In that case, the optimizer would fulfil condition (1.), the result of that would be pretty-printed when writing the bundle to disk, fulfilling (2.). When the bundle was then used, we'd satisfy (3.). As a workaround users may disable optimization when creating bundles.

Weakness: CWE-682

Which versions are affected by CVE-2022-23628?

3 open source packages ship an affected version, including github.com/open-policy-agent/opa. It affects 1 product.

Products include Openpolicyagent Open Policy Agent.

How do I fix CVE-2022-23628?

Upgrade github.com/open-policy-agent/opa to 0.37.2 or later.

Is CVE-2022-23628 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-23628 exists.

Other vulnerabilities in open-policy-agent opa

• CVE-2022-33082 Denial of service in Open Policy Agent High 7.5
• CVE-2022-28946 Out of bounds memory access in github.com/open-policy-agent/opa High 7.5
• CVE-2022-36085 OPA Compiler: Bypass of WithUnsafeBuiltins using `with` keyword to mock functions High 7.4
• CVE-2024-8260 OPA SMB Force-Authentication Medium 6.1

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-hcw3-j74m-qc58, GO-2022-0316.