CVE-2026-20253

Published Jun 10, 2026

Last updated 7 days ago

Exploit known CVSS critical 9.8

Splunk

Network

Server

Database

Overview

AI description

Automated description summarized from trusted sources.

CVE-2026-20253 is a vulnerability affecting Splunk Enterprise and Splunk Cloud Platform, stemming from a lack of authentication controls in the PostgreSQL sidecar service endpoint. This flaw permits any network-reachable, unauthenticated user to perform file operations, specifically creating or truncating arbitrary files on the affected system. The vulnerability exists in Splunk Enterprise versions below 10.2.4 and 10.0.7, and Splunk Cloud Platform versions below 10.4.2604.3 and 10.2.2510.14. This unauthenticated file manipulation can potentially lead to unauthorized data tampering or disruption of service.

Description: In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.
Source: psirt@cisco.com
NVD status: Analyzed
Products: splunk

Risk scores

CVSS 3.1

Type: Secondary
Base score: 9.8
Impact score: 5.9
Exploitability score: 3.9
Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: CRITICAL

Known exploits

Data from CISA

Vulnerability name: Splunk Enterprise Missing Authentication for Critical Function Vulnerability
Exploit added on: Jun 18, 2026
Exploit action due: Jun 21, 2026
Required action: 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.

Weaknesses

psirt@cisco.com: CWE-306

Hype score: Not currently trending

Configurations

[
  {
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:splunk:splunk:*:*:*:*:enterprise:*:*:*",
            "matchCriteriaId": "0C9F1DED-280E-4C76-A867-A7A8FCBD1F7A",
            "versionEndExcluding": "10.0.7",
            "versionStartIncluding": "10.0.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:splunk:splunk:*:*:*:*:enterprise:*:*:*",
            "matchCriteriaId": "E3B992C0-AD5E-43A1-BAA3-6B11FFD5D750",
            "versionEndExcluding": "10.2.4",
            "versionStartIncluding": "10.2.0",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.