Actively exploited vulnerability

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.

CISA KEV source 18 Jun 2026 added 21 Jun 2026 remediation due

Affected product

Splunk · Enterprise

Known ransomware use: Unknown

Required action

Follow the source advisory and validate exposure in your environment.

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.

Related Yasna coverage

Recent reporting that mentions CVE-2026-20253.

Security Affairs19 Jun 2026

U.S. CISA adds Splunk Enterprise flaw to its Known Exploited Vulnerabilities catalog and urges agencies to fix it by Sunday

U.S. Cybersecurity and Infrastructure Security Agency (CISA) adds Splunk Enterprise flaw to its Known Exploited Vulnerabilities catalog. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added a Splunk Enterprise flaw, tracked as CVE-2026-20253 (CVSS score of 9.8), to its Known Exploited Vulnerabilities (KEV) catalog. The flaw CVE-2026-20253 is an improper authentication vulnerability in the PostgreSQL sidecar service of […]