CVE entry · CVE-2026-20253
CVE-2026-20253: Splunk Enterprise Missing Authentication for Critical Function Vulnerability
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.
- Actively exploited: added to CISA’s KEV catalog on June 18, 2026.
- Use by ransomware: not established so far.
- Remediation deadline for US federal agencies: June 21, 2026.
Description from CISA’s KEV catalog.
What to do
- Check whether your estate includes Splunk Enterprise, including internet-facing devices.
- Apply the vendor’s patch or mitigations (references below). Failing that, isolate the product or stop using it, as CISA requires of US federal agencies.
- An exploited vulnerability has often been used before it was fixed: look for signs of compromise, especially on internet-facing devices.
References
- Vendor advisory or reference cited by CISA (advisory.splunk.com)
- NVD entry (NIST)
- CISA KEV catalog