Cleartext Storage of Sensitive Information in an Environment Variable in Elastic Cloud on Kubernetes Leading to Information Disclosure
Cleartext Storage of Sensitive Information in an Environment Variable (CWE-526) in Elastic Cloud on Kubernetes (ECK) can lead to information disclosure via Retrieve Embedded Sensitive Data (CAPEC-37). When ECK reconciles a Fleet Server resource that authenticates to Elasticsearch with a service account token, the token is written into the generated workload specification in cleartext rather than being referenced from the Kubernetes Secret that ECK maintains for the other credentials on the same path. Any principal able to read workload specifications in the affected namespace can therefore read a live Elasticsearch credential, even when Kubernetes RBAC does not grant that principal access to Secrets.
Affected Versions:
- 3.x: All versions from 3.0.0 up to and including 3.4.1
Release lines earlier than 3.x are no longer maintained and do not receive fixes. Users on those lines should upgrade to 3.5.0.
Affected Configurations:
- ECK-managed Elastic Agent resources with Fleet Server enabled.
Solutions and Mitigations:
The issue is resolved in version 3.5.0.
Because the credential may already have been readable by any principal with read access to workloads in the affected namespace, Elastic recommends invalidating the affected Elasticsearch service account token and issuing a replacement after upgrading.
For Users that Cannot Upgrade:
There are no workarounds.
Indicators of Compromise (IOC)
No specific indicators of compromise have been identified for this vulnerability.
Severity: CVSSv3.1: Medium ( 6.5 ) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVE ID: CVE-2026-72648
Problem Type: CWE-526 - Cleartext Storage of Sensitive Information in an Environment Variable
Impact: CAPEC-37 - Retrieve Embedded Sensitive Data