PT-2026-31659 · Unknown+1 · Clickhouseuser+2

Published 2026-04-09 · Updated 2026-05-13 · CVE-2026-39961

Positive Technologies (AI Summary)

CVSS v3.1

6.8

Medium

Base vector

AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N

Name of the Vulnerable Software and Affected Versions Aiven Operator versions 0.31.0 through 0.36.9

Description Aiven Operator allows provisioning and management of Aiven Services from a Kubernetes cluster. A developer with create permission on ClickhouseUser Custom Resource Definitions (CRDs) in their own namespace can exfiltrate secrets from any other namespace – production database credentials, API keys, service tokens – with a single kubectl apply. The operator reads the victim's secret using its ClusterRole and writes the password into a new secret in the attacker's namespace. The operator acts as a confused deputy, trusting user-supplied namespace values in spec.connInfoSecretSource.namespace without validation. No admission webhook enforces this boundary.

Recommendations Update to Aiven Operator version 0.37.0 or later.

Fix

Improper Privilege Management

Weakness Enumeration

CWE-441

CWE-269

Related Identifiers

CVE-2026-39961

GHSA-99J8-WV67-4C72

Affected Products

Aiven-Operator

Clickhouseuser

Kubernetes

References · 9

• https://github.com/aiven/aiven-operator/commit/032c9ba63257fdd2fddfb7f73f71830e371ff182 · Patch
• https://github.com/aiven/aiven-operator/security/advisories/GHSA-99j8-wv67-4c72 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39961 · Security Note
• https://osv.dev/vulnerability/GHSA-99j8-wv67-4c72 · Vendor Advisory
• https://github.com/aiven/aiven-operator/releases/tag/v0.37.0 · Note
• https://github.com/aiven/aiven-operator · Note
• https://reddit.com/r/kubernetes/comments/1shkpf0/psa_if_your_k8s_operators_have_clusterrole_secret · Reddit Post
• https://t.me/cveNotify/163320 · Telegram Post
• https://twitter.com/_cvereports/status/2049068831662879072 · Twitter Post