CVE-2022-23628 Information

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.

CVSS Vector

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

Reference

https://github.com/open-policy-agent/opa/pull/3851 https://github.com/open-policy-agent/opa/security/advisories/GHSA-hcw3-j74m-qc58 https://github.com/open-policy-agent/opa/commit/bfd984ddf93ef2c4963a08d4fdadae0bcf1a3717 https://github.com/open-policy-agent/opa/commit/932e4ffc37a590ace79e9b75ca4340288c220239

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

LOW

Base Score

NONE

Base Severity

5.3