Full Report
Splunk has released security updates to address a critical security flaw in Splunk Enterprise that could be exploited to conduct unauthenticated file operations and even remote code execution. The vulnerability, tracked as CVE-2026-20253, is rated 9.8 on the CVSS scoring system. "In Splunk Enterprise versions below 10.2.4 and 10.0.7, an unauthenticated user could create or truncate arbitrary
Analysis Summary
# Vulnerability: Pre-Authentication Remote Code Execution in Splunk Enterprise
## CVE Details
- **CVE ID:** CVE-2026-20253
- **CVSS Score:** 9.8 (Critical)
- **CWE:** Missing Authentication for Critical Function (CWE-306) / Path Traversal (CWE-22)
## Affected Systems
- **Products:** Splunk Enterprise
- **Versions:**
- 10.0.0 to 10.0.6
- 10.2.0 to 10.2.3
- **Configurations:** Systems utilizing the PostgreSQL sidecar service; Splunk Cloud is **not** affected.
## Vulnerability Description
A critical flaw exists in the PostgreSQL sidecar service endpoints (`/v1/postgres/recovery/backup` and `/v1/postgres/recovery/restore`) which lack proper authentication controls. An unauthenticated, network-reachable attacker can invoke these endpoints to perform arbitrary file operations. Specifically, the vulnerability allows for the creation or truncation of files by manipulating the database restoration process and leveraging arguments like `passfile` to bypass internal database security.
## Exploitation
- **Status:** PoC available (Technical details and attack chain published by watchTowr Labs). No evidenced exploitation in the wild at the time of the report.
- **Complexity:** Medium
- **Attack Vector:** Network
## Impact
- **Confidentiality:** High (Full access to local database and system files)
- **Integrity:** High (Ability to overwrite critical Python scripts and modify system behavior)
- **Availability:** High (Potential to truncate files or crash services)
## Remediation
### Patches
Update to the following versions as released by the vendor:
- Splunk Enterprise **10.0.7** or higher
- Splunk Enterprise **10.2.4** or higher
- Splunk Enterprise **10.4** is not affected.
### Workarounds
- Restrict network access to Splunk Enterprise management ports to trusted IP addresses only.
- Disable the PostgreSQL sidecar service if it is not required for your specific deployment (consult Splunk documentation for environmental impact).
## Detection
- **Indicators of Compromise:**
- Unexpected HTTP POST requests to `/v1/postgres/recovery/backup` or `/v1/postgres/recovery/restore` from unauthorized or external IP addresses.
- Presence of unauthorized `.pgpass` files in `/opt/splunk/var/packages/data/postgres/`.
- Unusual modifications to Splunk Python scripts, such as `/opt/splunk/etc/apps/splunk_secure_gateway/bin/ssg_enable_modular_input.py`.
- **Detection methods and tools:** Monitor web server access logs for the specific PostgreSQL sidecar endpoints and use File Integrity Monitoring (FIM) for the Splunk installation directory.
## References
- Splunk Advisory SVD-2026-0603: hxxps[://]advisory[.]splunk[.]com/advisories/SVD-2026-0603
- watchTowr Labs Research: hxxps[://]labs[.]watchtowr[.]com/why-use-app-level-auth-when-every-database-has-auth-splunk-enterprise-cve-2026-20253-pre-auth-rce/
- The Hacker News Article: hxxps[://]thehackernews[.]com/2026/06/critical-splunk-enterprise-flaw-lets.html