Vulnerability record

CVE-2026-20253

Splunk Enterprise Missing Authentication for Critical Function Vulnerability

Severity: CriticalExploitation: Exploitation confirmedCISA KEV
What should I do?

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Enterprise, fix it now.

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.

US federal civilian agencies must remediate by Jun 21, 2026.

Patch status

No official fix confirmed yet

Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.

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: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.

Affected products

Products affected by this vulnerability, with versions and the source of each entry
ProductVendorSource
EnterpriseSplunkKEV

Sources: KEV = CISA Known Exploited Vulnerabilities catalog. Version details have not been published yet.

Intelligence timeline

Developments from the last 30 days, newest first.

No developments recorded for CVE-2026-20253 in the last 30 days.

1 earlier event is available with a subscription. See plans.

Coverage

We have not published a story about this vulnerability yet.

References

  • advisory.splunk.com https://advisory.splunk.com/advisories/SVD-2026-0603
  • cisa.gov https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
  • cisa.gov https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-ba…
  • nvd.nist.gov https://nvd.nist.gov/vuln/detail/CVE-2026-20253
  • labs.watchtowr.com https://labs.watchtowr.com/why-use-app-level-auth-when-every-database-has-auth-splunk-enterprise-cve-2026-2025…
  • cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20253