CVE-2026-20253KEV · OVERDUECWE-306

Unauthenticated Arbitrary File Creation and Truncation in a PostgreSQL Sidecar Service Endpoint in Splunk Enterprise

Critical · published June 10, 2026

Patch now

Confirmed exploited, and the score agrees

CVSS calls it critical at 9.8. It is confirmed in active exploitation. It sits in the 99.9th percentile for exploit probability.

125
days past CISA
deadline
CVSS v3.1
9.8
EPSS
97%
Percentile
99.9
In the wild
Confirmed
What it is

🚨 An unauthenticated user can wield the power to create or delete files on your Splunk server, thanks to a sneaky PostgreSQL sidecar service vulnerability! 🔥 Think of it as a restaurant where anyone can waltz into the kitchen and cook whatever they want, or worse, toss out the chef's special! Without proper authentication controls, this endpoint is like an open door to file operations for anyone on the network. This is absolutely devastating! An attacker could exploit this flaw to compromise the integrity of your entire file system, creating, altering, or truncating any files at will. Imagine the chaos if sensitive data was deleted or tampered with—your operations could be thrown into disarray!

Put simply

Think of it as a restaurant where anyone can waltz into the kitchen and cook whatever they want, or worse, toss out the chef's special! Without proper authentication controls, this endpoint is like an open door to file operations for anyone on the network. In Splunk Enterprise versions 10.2 below 10.2.4 and 10.0 below 10.0.7, the PostgreSQL sidecar service endpoint lacks necessary authentication, allowing unauthenticated users to execute arbitrary file operations without any credentials.

What to do

This is absolutely devastating! An attacker could exploit this flaw to compromise the integrity of your entire file system, creating, altering, or truncating any files at will. Imagine the chaos if sensitive data was deleted or tampered with—your operations could be thrown into disarray! Upgrade immediately to Splunk Enterprise version 10.2.4 or 10.0.7 and ensure that your PostgreSQL sidecar service is secured. If you can't upgrade right away, disable the PostgreSQL sidecar service as a temporary measure to mitigate this critical risk. You've got this! Follow these steps and you'll lock down your Splunk environment in no time! 🛡️

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.96939 · 99.9th percentile
Weakness
CWE-306 · Missing Authentication for Critical Function
Published
2026-06-10T17:16Z
KEV added
2026-06-18 · due 2026-06-21
EPSS history
Timeline
  • 18 JUN 00:00Z
    Added to CISA KEV — remediate by Jun 21
    kev
  • 10 JUN 17:16Z
    Unauthenticated Arbitrary File Creation and Truncation in a PostgreSQL Sidecar Service Endpoint in Splunk Enterprise
    cvelistv5