CVE-2026-76267 Splunk CVE debrief

Who should care

Defenders responsible for Splunk Enterprise deployments, particularly those with users holding the read_o11y_content capability, should assess exposure and prioritize mitigation. They should verify affected versions, restrict access, and monitor logs for potential log injection attacks. Defenders should also review compensating controls for exposed systems while remediation is scheduled and verified.

Why it matters

A log injection vulnerability in Splunk Enterprise allows users with specific capabilities to inject forged log entries, potentially leading to security issues. Defenders should verify affected versions, restrict access, and monitor logs.

• Potential log injection attacks through the REST API
• Verification of affected Splunk Enterprise versions and user capabilities
• Monitoring app logs for suspicious activity

Technical summary

The Splunk App for Splunk O11y Cloud does not neutralize user-supplied SignalFlow content before writing it to the app log, allowing users with the read_o11y_content capability to inject forged entries into the app log through the REST API. This vulnerability could lead to potential log injection attacks, emphasizing the need for defenders to verify affected versions and mitigate the vulnerability. Defenders should prioritize verifying affected versions and mitigating the vulnerability to prevent potential log injection attacks.

Defensive priority

Defenders should prioritize verifying affected versions and mitigating the vulnerability to prevent potential log injection attacks.

Recommended defensive actions

• Verify affected Splunk Enterprise versions and apply patches or updates
• Restrict access to the REST API for users with the read_o11y_content capability
• Monitor app logs for potential log injection attacks
• 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 confirmed in Splunk Enterprise versions below 10.4.3, 10.2.7, and 10.0.10. Users with the read_o11y_content capability can inject forged entries into the app log through the REST API. Defenders should verify affected versions, restrict access, and monitor logs for potential log injection attacks. The vulnerability allows users with specific capabilities to inject forged log entries, potentially leading to security issues.

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.