The destructor of the JSON Object in Envoy can trigger a stack overflow when processing an object hierarchy that is over 100,000 levels deep. This stack‑based buffer overflow (CWE‑1124) can corrupt control data, causing an Envoy process to terminate unexpectedly. The immediate outcome is a denial of service to any service relying on that Envoy instance.

Affected versions are Envoy deployments older than 1.35.11, 1.36.7, 1.37.3, and 1.38.1. Any instance that loads deeply nested JSON, such as complex configuration files, can be vulnerable if running those releases.

The CVSS score of 7.5 reflects a high severity for a denial‑of‑service flaw. No EPSS data is available, and the vulnerability is not listed in the CISA KEV catalog, so the likelihood of exploitation in the wild is uncertain. The likely attack vector is an attacker supplying a deeply nested JSON configuration that is processed by Envoy, causing the stack overflow during object destruction. A malformed configuration could lead to a crash and service disruption.