CVE-2026-20253

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.

Scoring

• CVSS: 9.8 (CRITICAL, 3.1)
• EPSS exploitation probability: Not yet available
• EPSS percentile: Not yet available

CISA KEV status

• Added to KEV: 2026-06-18
• Remediation due date: 2026-06-21
• Known ransomware campaign use: Unknown

Weakness types (CWE)

• CWE-306

References

• https://advisory.splunk.com/advisories/SVD-2026-0603
• https://labs.watchtowr.com/why-use-app-level-auth-when-every-database-has-auth-splunk-enterprise-cve-2026-20253-pre-auth-rce/
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20253

More from Splunk

• No other tracked CVEs for this vendor yet.