CVE-2026-79754 in Nuclio
Summary
by MITRE • 09/02/2026
Nuclio is a "Serverless" framework for Real-Time Events and Data Processing. From version 1.6.19 to before version 1.17.2, Nuclio's Dashboard build pipeline does not sanitize the spec.build.tempDir field before using it to construct a shell command. When the Kaniko container builder is enabled, a user with function-create permission can inject shell metacharacters into this field and achieve arbitrary command execution inside the Dashboard container, which runs with a Kubernetes service account holding wildcard access to Secrets, Pods, Jobs, and Deployments in its namespace. This issue has been patched in version 1.17.2.
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Analysis
by VulDB Data Team • 09/02/2026
Nuclio is an open-source serverless framework designed for real-time event processing and data streaming applications. A critical security vulnerability was identified within the Nuclio Dashboard component, specifically affecting versions from 1.6.19 up to but not including version 1.17.2. The core of this issue lies in a command injection flaw that arises during the function build process when the Kaniko container builder is enabled. Kaniko is an open-source tool used for building container images inside Kubernetes or OpenShift clusters without requiring a Docker daemon, and Nuclio utilizes it to construct image artifacts from user-defined source code and configuration specifications.
The technical root cause of this vulnerability is insufficient input sanitization applied to the spec.build.tempDir field within the function specification object. When a user submits a request to create or update a function with Kaniko enabled, the Dashboard backend constructs shell commands to invoke the Kaniko builder. The tempDir parameter, which specifies where temporary build files should be stored, was passed directly into these shell command strings without proper validation or escaping of special characters. This lack of sanitization allows an attacker who has permission to create functions to inject arbitrary shell metacharacters and commands into the execution context of the Dashboard container.
The operational impact of this vulnerability is severe due to the privilege level associated with the Nuclio Dashboard service account in typical Kubernetes deployments. The dashboard typically runs under a ServiceAccount that possesses wildcard access (wildcard permissions) to critical resources such as Secrets, Pods, Jobs, and Deployments within its namespace. Consequently, successful exploitation allows an attacker to achieve arbitrary command execution inside the Dashboard container. From this foothold, the attacker can leverage the high-privilege service account to exfiltrate sensitive data stored in Kubernetes secrets, manipulate running workloads by creating or deleting pods and jobs, and potentially escalate privileges further within the cluster environment. This represents a significant breach of confidentiality, integrity, and availability for applications relying on Nuclio for serverless processing.
This vulnerability aligns with Common Weakness Enumeration (CWE) category CWE-78: Improper Neutralization of Special Elements used in an OS Command, commonly known as OS Command Injection. In terms of the MITRE ATT&CK framework, this exploit maps to T1059: Command and Scripting Interpreter, specifically allowing for remote code execution via injected shell commands. It also relates to privilege escalation vectors where initial access through a lower-privileged user leads to control over higher-value resources due to overly permissive service account bindings.
To mitigate this risk, organizations running Nuclio versions prior to 1.17.2 must upgrade immediately to version 1.17.2 or later, which includes the necessary code changes to properly sanitize input fields before shell command construction. In environments where upgrading is not immediately feasible, administrators should restrict the permissions of the ServiceAccount used by the Nuclio Dashboard. Applying least-privilege principles by removing wildcard access to Secrets and other sensitive resources can significantly reduce the blast radius if an injection attempt occurs. Additionally, implementing network policies to limit outbound traffic from the dashboard container and enforcing strict input validation at the API gateway level can provide defense-in-depth measures against such command injection attacks.