---
id: "CVE-2026-20253"
kind: "vulnerability"
aliases: ["CVE-2026-20253"]
title: "In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create\u2026"
severity: "critical"
cvss: 9.8
epss: null
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Splunk Enterprise", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "splunk", "fixed": ["10.0.7"], "affected": ">= 10.0.0, < 10.0.7", "ecosystem": "vendor"}, {"name": "splunk", "fixed": ["10.2.4"], "affected": ">= 10.2.0, < 10.2.4", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "self-hosted", "splunk-enterprise", "vendor"]
not_affected_if: ["managed-hosting"]
published_at: "2026-06-10T18:16:40+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-20253", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-20253", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create…

Splunk Enterprise has a missing authentication flaw in a critical function that lets an unauthenticated user create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. CISA lists it as actively exploited in the wild.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Splunk Enterprise affected ? fixed ?
- vendor:splunk affected >= 10.0.0, < 10.0.7 fixed 10.0.7
- vendor:splunk affected >= 10.2.0, < 10.2.4 fixed 10.2.4

## Fix

Apply the mitigation or patch from Splunk's vendor advisory for CVE-2026-20253; the sources do not name the fixed version. If no mitigation is available, discontinue use of the affected product per CISA BOD 26-04 guidance.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-20253
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-20253

## From the sources

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 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.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_