Exploited vulnerability · CISA KEV

Is CVE-2026-20253 exploited? Yes: in CISA KEV since 18 Jun 2026

Gociux · Splunk Enterprise · data: CISA KEV, CVE record, FIRST EPSS

Yes. CVE-2026-20253, Splunk Enterprise Missing Authentication for Critical Function Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 18 Jun 2026, 8 days after it was published. It affects Splunk Enterprise. If you run it, CISA's required action is: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

What it is

Splunk Enterprise contains a missing authentication for critical function vulnerability which could allow an unauthenticated user to create or truncate arbitrary files through a PostgreSQL sidecar service endpoint.

What to do

1. Check whether you run it. Look for Enterprise in your asset inventory, including appliances and cloud images. Stack check lists every exploited Splunk CVE at once.
2. Apply the fix. Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
3. If you can't patch today, take the affected service off the internet or restrict who can reach it, and check its logs for signs of compromise since 10 Jun 2026.
4. Get told next time. Email alerts when CISA adds a CVE for Splunk.

References

• advisory.splunk.com/advisories/SVD-2026-0603
• nvd.nist.gov/vuln/detail/CVE-2026-20253

Sources: CISA KEV (exploitation, ransomware use, required action, due date), the CVE record (publication date, CVSS, CNA), NVD and FIRST EPSS (live score). More: all KEV additions in June 2026 · act-now radar.