CVE-2023-27484: Unchecked fieldpath index in Composition's patches can lead to arbitrary memory allocation in crossplane
crossplane-runtime is a set of go libraries used to build Kubernetes controllers in Crossplane and its related stacks. In affected versions an already highly privileged user able to create or update Compositions can specify an arbitrarily high index in a patch's ToFieldPath, which could lead to excessive memory usage once such Composition is selected for a Composite resource. Compositions allow users to specify patches inserting elements into arrays at an arbitrary index. When a Composition is selected for a Composite Resource, patches are evaluated and if a specified index is greater than the current size of the target slice, Crossplane will grow that slice up to the specified index, which could lead to an excessive amount of memory usage and therefore the Pod being OOM-Killed. The index is already capped to the maximum value for a uint32 (4294967295) when parsed, but that is still an unnecessarily large value. This issue has been addressed in versions 1.11.2, 1.10.3, and 1.9.2. Users are advised to upgrade. Users unable to upgrade can restrict write privileges on Compositions to only admin users as a workaround.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2023-27484?
The severity of CVE-2023-27484 is considered high due to its impact on privileged user actions.
How do I fix CVE-2023-27484?
To fix CVE-2023-27484, you should upgrade to Crossplane version 1.9.3, 1.10.4, or 1.11.3 or later.
Who is affected by CVE-2023-27484?
CVE-2023-27484 affects Crossplane users on versions 1.9.0 to 1.9.2, 1.10.0 to 1.10.3, and 1.11.0 to 1.11.2.
What does CVE-2023-27484 exploit?
CVE-2023-27484 exploits the ability of a highly privileged user to specify an arbitrary index in a patch's ToFieldPath, potentially leading to unauthorized changes.
When was CVE-2023-27484 disclosed?
CVE-2023-27484 was disclosed in 2023 as part of ongoing security assessments for Crossplane.