CVE-2026-76276 in Splunk
Summary
by MITRE • 10/07/2026
In Splunk Enterprise versions below 10.4.3, 10.2.7, and 10.0.10, a low-privileged user that does not hold the "admin" or "power" Splunk roles could retrieve original source code for the Discover Splunk Observability Cloud app through Splunk Web. The vulnerability is possible because production JavaScript bundles for the app contain embedded source maps that include original source code. For more information see About configuring role-based user access (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/about-configuring-role-based-user-access), Splunk Observability Cloud previews (https://help.splunk.com/en/splunk-enterprise/search/search-manual/10.4/observability/splunk-observability-cloud-previews), and Navigating Splunk Web (https://help.splunk.com/en/splunk-enterprise/search/search-tutorial/10.4/part-1-getting-started/navigating-splunk-web) in the Splunk documentation.
Splunk Enterprise versions 9.4.x are not affected.
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Analysis
by VulDB Data Team • 10/07/2026
A significant information disclosure vulnerability exists within specific legacy releases of Splunk Enterprise, specifically those prior to version 10.4.3, 10.2.7, and 10.0.10. This flaw allows low-privileged users who lack administrative or power-level roles to access sensitive internal data through the standard web interface known as Splunk Web. The core of this vulnerability lies in the deployment configuration of the Discover Splunk Observability Cloud application integrated within the platform. During development, source maps are typically generated to assist developers in debugging JavaScript code by mapping minified bundles back to their original source files. In a secure production environment, these source maps should be stripped or disabled to prevent exposure of proprietary logic and internal structures. However, in the affected versions, the production JavaScript bundles for this specific application inadvertently retained embedded source maps that contained the full original source code.
The technical mechanism enabling this exploitation is straightforward yet impactful. When an authenticated user accesses the Splunk Web interface and interacts with the Discover Splunk Observability Cloud app, the browser requests various static assets including JavaScript files. Due to the misconfiguration where source maps are included in these production bundles, a malicious actor or any low-privileged user can request the corresponding .map file associated with the application's scripts. By parsing this map file, which is essentially JSON containing mappings between minified code and original source locations, the attacker can reconstruct the unminified JavaScript source code. This process does not require elevated privileges because it relies solely on reading publicly accessible static assets served by the web server component of Splunk Enterprise, bypassing role-based access controls that would normally restrict sensitive data retrieval.
The operational impact of this vulnerability centers on intellectual property exposure and potential secondary exploitation vectors. The exposed source code may contain proprietary algorithms, internal API endpoints, authentication handling logic, or integration details with Splunk Observability Cloud services. While the immediate risk is classified as information disclosure, leaked source code can provide attackers with valuable insights into the application's architecture. This knowledge could facilitate further attacks such as identifying unpatched flaws within the JavaScript logic, crafting targeted phishing campaigns based on internal workflows, or understanding how sensitive data flows through the observability pipeline. For organizations relying on Splunk for critical security monitoring and operational intelligence, the exposure of proprietary code undermines trust in the platform's security posture and may violate compliance requirements regarding intellectual property protection.
To mitigate this risk, administrators must upgrade to a patched version of Splunk Enterprise immediately. The vulnerability is resolved in versions 10.4.3, 10.2.7, and 10.0.10, as well as all subsequent releases where the build process correctly excludes source maps from production deployments. For environments running Splunk Enterprise version 9.4.x or earlier, this specific vulnerability does not apply due to architectural differences in how applications are packaged and served. In addition to upgrading, organizations should audit their deployment configurations for any custom apps that might also expose source maps in production builds. Implementing strict Content Security Policy headers can further reduce the risk of exploitation by limiting where scripts can be loaded from, although this is a compensating control rather than a fix for the root cause.
From a classification perspective, this vulnerability aligns with CWE-200: Information Exposure, which covers scenarios where sensitive information is disclosed to unauthorized actors without necessarily being modified or destroyed. It also relates to CWE-359: Exposed Private Personal Information if any user-specific data were inadvertently included in the source maps, though primarily it concerns code exposure. In terms of adversary tactics, this aligns with ATT&CK technique T1087: Account Discovery and potentially T1602: Software Packaging Tool Impersonation if attackers use the retrieved code to craft malicious tools that mimic legitimate Splunk components for phishing or lateral movement purposes. The lack of authentication requirements for accessing static assets highlights a common misconfiguration in web application development where build artifacts are not properly sanitized before deployment, emphasizing the need for rigorous CI/CD pipeline security checks to ensure production builds do not contain debug information.