Auth bypass in Elastic Elasticsearch

CVE-2026-78607

Missing Authorization (CWE-862) in the Elasticsearch custom inference service can lead to information disclosure via Privilege Abuse (CAPEC-122). A user holding only inference execution privileges could cause outbound inference traffic to be directed to a destination of their choosing and could cause administrator-provisioned credentials to be exposed.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-78607: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-78607?
CVE-2026-78607 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Missing Authorization. CVSS score: 5.4/10. Published 2026-09-01.
How severe is CVE-2026-78607?
Medium severity. CVSS v3 base score is 5.4 out of 10.