CVE-2022-23628: OPA is an open source, general-purpose policy engine. Under certain conditions, pretty-printing an abstract syntax tree (AST) that contains synthetic ...

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.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS Probability

1.02%

59.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-682

Affected Software

Vendor	Product	Versions
Openpolicyagent	Open Policy Agent	>= 0.33.1, < 0.37.0

References

https://github.com/open-policy-agent/opa/commit/932e4ffc37a590ace79e9b75ca4340288c220239Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/commit/bfd984ddf93ef2c4963a08d4fdadae0bcf1a3717Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/pull/3851Issue Tracking, Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/security/advisories/GHSA-hcw3-j74m-qc58Exploit, Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/commit/932e4ffc37a590ace79e9b75ca4340288c220239Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/commit/bfd984ddf93ef2c4963a08d4fdadae0bcf1a3717Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/pull/3851Issue Tracking, Patch, Third Party Advisory
https://github.com/open-policy-agent/opa/security/advisories/GHSA-hcw3-j74m-qc58Exploit, Patch, Third Party Advisory

Timeline

Published: Feb 9, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-23628?

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.

How severe is CVE-2022-23628?

CVE-2022-23628 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 1.02% probability of exploitation in the next 30 days.

How do I fix CVE-2022-23628?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.