Memory Allocation with Excessive Size Value, classified as CWE‑789, is present in the Prometheus remote_write HTTP handler in Elastic Metricbeat. An attacker can target the remote_write endpoint with a specially crafted request that causes the application to allocate an excessively large amount of memory, leading to service interruption. The vulnerability exposes only availability loss; there is no indication that confidentiality or integrity is directly compromised.

The vulnerability is reported for Elastic Metricbeat. No specific version range is supplied in the data, so all installations that have not applied a patch may be affected. Users should check their deployed Metricbeat version against recent Elastic advisories, as newer releases may already contain a fix.

The CVSS score is 5.7, indicating a moderate severity level. EPSS data is not available, and the vulnerability is not listed in the CISA KEV catalog, suggesting moderate likelihood of exploitation but limited existing evidence of widespread attacks. The attack vector is inferred to be remote, delivered via an external HTTP request to the remote_write endpoint, which can be performed over the network without authentication in many default configurations.