CVE-2026-20253: Splunk Arbitrary File Write

How CVE-2026-20253 Turns Splunk’s PostgreSQL Sidecar Into an Open Door

CVE-2026-20253 is a CVSS 9.8 pre-auth flaw in Splunk Enterprise's PostgreSQL sidecar service. An unauthenticated attacker can write files and chain the primitive to RCE. A public PoC exists; no workaround, patch only. How CVE-2026-20253 Turns Splunk’s PostgreSQL Sidecar Into an Open Door on Latest Hacking News | Cyber Security News, Hacking Tools and Penetration Testing Courses.

CVE-2026-20253: Splunk Arbitrary File Write

Splunk has disclosed CVE-2026-20253, a critical unauthenticated arbitrary file write vulnerability affecting Splunk Enterprise. The flaw exists in a PostgreSQL sidecar service endpoint that lacks authentication controls, allowing a network-reachable attacker to create or truncate arbitrary files on the underlying host without credentials. The vulnerability carries a CVSS v3.1 score of 9.8… Source