CVE-2026-76397: Splunk AI Toolkit Privilege Escalation

CVE-2026-76397 Overview

CVE-2026-76397 is an authorization bypass vulnerability in Splunk AI Toolkit versions below 6.0.0. A user assigned the power Splunk role can access and delete experiment history data belonging to other users. The flaw exists because Splunk AI Toolkit fails to preserve the trusted experiment scope when processing caller-controlled query values before accessing restricted history data. The issue is categorized as an Insecure Direct Object Reference through user-controlled key manipulation [CWE-639].

Critical Impact
An authenticated power role user can read and destroy experiment history records owned by other users, resulting in cross-tenant data disclosure and integrity loss in shared Splunk AI Toolkit deployments.

Affected Products

Splunk AI Toolkit versions prior to 6.0.0
Splunk deployments using the Experiment Assistants feature
Shared multi-user Splunk environments with power role assignments

Discovery Timeline

2026-08-19 - CVE-2026-76397 published to NVD
2026-08-20 - Last updated in NVD database

Technical Details for CVE-2026-76397

Vulnerability Analysis

The vulnerability resides in how Splunk AI Toolkit handles experiment history requests. The toolkit accepts query values supplied by the caller and uses those values to look up history records without re-verifying that the requesting user owns the referenced experiment. As a result, the trusted experiment scope established at session context is discarded during query processing.

A user holding the power Splunk role can craft requests that reference experiment identifiers belonging to other users. The application returns and modifies those records because access decisions rely on the attacker-supplied identifier rather than the authenticated user's authorization boundary. Both confidentiality and integrity of experiment history are affected.

Root Cause

The root cause is improper enforcement of authorization on user-controlled input, classified as [CWE-639] Authorization Bypass Through User-Controlled Key. Splunk AI Toolkit trusts caller-supplied query values when locating restricted history data instead of validating the record against the authenticated user's scope.

Attack Vector

Exploitation requires network access to the Splunk interface and valid credentials with the power role. No user interaction is required. The attacker submits requests to the Experiment Assistants functionality with modified identifiers to enumerate or delete history entries owned by other users. Refer to the Splunk Security Advisory SVD-2026-0808 for vendor technical details.

Detection Methods for CVE-2026-76397

Indicators of Compromise

Unexpected deletion or modification of experiment history records in the Splunk AI Toolkit
Access log entries showing power role users querying experiment identifiers they did not create
Anomalous request volume from a single power role account targeting Experiment Assistants endpoints

Detection Strategies

Correlate experiment history read and delete events against the owning user identity and flag mismatches
Review Splunk audit logs for calls to Experiment Assistants endpoints made by accounts that do not own the referenced experiment
Baseline normal Experiment Assistants activity per user and alert on deviations in access patterns

Monitoring Recommendations

Enable and forward _audit index events covering Splunk AI Toolkit REST endpoints to a centralized SIEM
Track deletion actions on experiment history and require review when performed by non-admin roles
Monitor role assignments and revoke power privileges that are not operationally required

How to Mitigate CVE-2026-76397

Immediate Actions Required

Upgrade Splunk AI Toolkit to version 6.0.0 or later
Audit current assignments of the power role and remove the role from users who do not require it
Review experiment history for unauthorized access or deletions since the toolkit was deployed

Patch Information

Splunk has addressed the vulnerability in Splunk AI Toolkit version 6.0.0. Consult the Splunk Security Advisory SVD-2026-0808 for full remediation guidance and version compatibility notes.

Workarounds

Restrict the power role to trusted administrators until the upgrade to 6.0.0 is complete
Disable or limit access to the Splunk AI Toolkit Experiment Assistants feature where feasible
Segregate sensitive experiments into separate Splunk apps or indexes with tighter role-based access controls

bash

# Configuration example: identify users assigned the power role
# Run from the Splunk search bar to enumerate power role members
| rest /services/authentication/users \
| search roles=power \
| table title, roles, email