CVE-2026-76303 Splunk CVE debrief

Who should care

Defenders who manage Splunk SOAR installations, especially those with users who have the install_apps capability, should assess exposure and prioritize remediation. They should verify and remediate vulnerable Splunk SOAR versions, restrict the install_apps capability to trusted users, and monitor for suspicious app documentation changes.

Why it matters

Defenders should care about CVE-2026-76303 because it allows attackers to store malicious content in app documentation, which can be executed in the browsers of other users. This could lead to data access and modification, phishing attacks, and other security issues. Defenders should verify and remediate vulnerable Splunk SOAR versions, restrict the install_apps capability to trusted users, and monitor for suspicious app documentation changes.

• Potential data access and modification by attackers
• Possible phishing attacks against users with permission to view apps
• Required verification of vulnerable versions and user roles
• Potential for attackers to make changes that appear to come from legitimate users

Technical summary

The vulnerability exists in Splunk SOAR versions below 8.7.0 and is caused by a lack of sanitization of app documentation content before it is displayed. A user with the install_apps capability can store attacker-controlled content in app documentation, which can be executed in the browser of another user who views the app documentation. This could allow the first user to access data and make changes that the second user could make. The attacker must phish the affected user to trick them into initiating a request within their browser.

Defensive priority

Defenders should prioritize verifying and remediating this vulnerability, especially in environments where users have the install_apps capability.

Recommended defensive actions

• Verify and remediate vulnerable Splunk SOAR versions
• Restrict the install_apps capability to trusted users
• Monitor for suspicious app documentation changes
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is caused by a lack of sanitization of app documentation content before it is displayed. The attacker must phish the affected user to trick them into initiating a request within their browser.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.