CVE-2026-46385

A flaw was found in the Avro array and map decoding logic in Go Avro. The decoder failed to properly stop processing after encountering read errors while iterating over attacker-controlled block-count values, leading to excessive resource consumption. A remote unauthenticated attacker could exploit this issue using specially crafted Avro payloads causing denial of service, where the affected system's CPU is consumed indefinitely until the process is terminated.

This vulnerability affects Avro array and map decoding functionality in affected Go Avro libraries. Red Hat Product Security has assessed this issue as an Important severity vulnerability.

A remote unauthenticated attacker may supply specially crafted Avro payloads containing excessively large block-count values followed by truncated or invalid data. Because the decoder continued iterating after the underlying reader entered an error state, affected applications may consume excessive CPU resources for extended periods of time, potentially leading to denial of service.

The currently available analysis demonstrates CPU exhaustion and service disruption but does not demonstrate confidentiality or integrity impact. Therefore, Red Hat assessed the impact as limited to Availability (A:H).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Red Hat is not aware of a practical temporary workaround that fully mitigates this issue or meets Red Hat Product Security's standards for usability, deployment, applicability, or stability. Customers are advised to apply the relevant security updates when they become available.