Ethical Hacking News
A recent security vulnerability in Splunk Enterprise has been discovered, allowing attackers to execute remote code without authentication. Learn more about the attack chain and how to protect your organization.
Vulnerability discovered in Splunk Enterprise, rated 9.8 on CVSS scoring system. Lack of authentication controls in PostgreSQL sidecar service endpoint allows remote code execution without authentication. Affected versions: 10.2.4 and below, 10.0.7 and below; Splunk Cloud not impacted. Attack chain involves dumping database contents into an arbitrary file, loading it into a local PostgreSQL instance, and executing SQL queries to gain control. Attacker can escalate further to remote code execution by overwriting Python scripts in the Splunk file system.
A recent security vulnerability in Splunk Enterprise has been discovered, allowing attackers to execute remote code without authentication. The vulnerability, tracked as CVE-2026-20253, is rated 9.8 on the CVSS scoring system and poses a significant threat to organizations that rely on Splunk for monitoring and analytics.
The vulnerability exists because the PostgreSQL sidecar service endpoint in Splunk Enterprise lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. This means that an attacker could create or truncate arbitrary files through this endpoint, potentially leading to further exploitation.
According to Splunk, versions below 10.2.4 and 10.0.7 are affected by the vulnerability. However, it's worth noting that Splunk Cloud is not impacted by the vulnerability as Postgres sidecars are not used in the product.
The attack chain works as follows: an attacker connects to a controlled database, dumps its contents into an arbitrary file using the "/backup" endpoint, loads the dump into a local PostgreSQL instance using the "/restore" endpoint with a "passfile" argument that specifies the path to a ".pgpass" file containing the password for the "postgres_admin" user. The SQL queries defined in the database dump are then executed by Splunk's PostgreSQL instance.
The attack chain continues with the attacker defining a new function that uses the lo_export function to write attacker-controlled content to a file, following which the function gets executed during the restoration process. This allows the attacker to authenticate, restore attacker-controlled SQL, and interact with the local database.
Once the attacker has an arbitrary file write primitive on the Splunk file system, they can escalate further to remote code execution by overwriting a Python script that Splunk frequently executes (e.g., "/opt/splunk/etc/apps/splunk_secure_gateway/bin/ssg_enable_modular_input.py") to include malicious payload.
The entire sequence of actions is as follows: create a database and configure it such that a user can authenticate without a password and grant sufficient permissions to invoke functions like lo_export, use the "/backup" endpoint to drop a dump of the remote database onto the Splunk file system, use the "/restore" endpoint to load the malicious database dump, trigger execution of the malicious function during the restore process, and write an attacker-controlled Python script to the Splunk file system.
While there is no evidence of the flaw being exploited in the wild, the availability of the exploit specifics can be enough to drive threat actors to trigger opportunistic attempts. It's essential that users move quickly to apply the fixes to stay protected.
In conclusion, this critical vulnerability in Splunk Enterprise exposes remote code execution, and it's essential for organizations to take immediate action to patch their systems before attackers can exploit it. This article will provide a detailed analysis of the attack chain and the steps necessary to protect against this vulnerability.
Related Information:
https://www.ethicalhackingnews.com/articles/Critical-Vulnerability-in-Splunk-Enterprise-Exposes-Remote-Code-Execution-ehn.shtml
https://thehackernews.com/2026/06/critical-splunk-enterprise-flaw-lets.html
Published: Sat Jun 13 09:21:09 2026 by llama3.2 3B Q4_K_M
