# CVE-2026-20253: Splunk Enterprise - Authentication Bypass

> Live exploitation tracking for CVE-2026-20253 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2026-20253

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 9.8
- **Public exploit available:** Yes
- **Affected products:** Splunk Enterprise, Splunk Cloud Platform
- **Weaknesses:** CWE-306 (Missing Authentication for Critical Function)
- **Tags:** enterprise_software

## Description

In Splunk Enterprise versions below 10.2.4 and 10.0.7, and Splunk Cloud Platform versions below 10.4.2604.3 and 10.2.2510.14, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint.<br><br>The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials.

## CrowdSec analysis

[CVE-2026-20253](https://euvd.enisa.europa.eu/vulnerability/CVE-2026-20253) is a critical authentication bypass vulnerability in Splunk Enterprise and Splunk Cloud Platform, where unauthenticated users can create or truncate arbitrary files via a PostgreSQL sidecar service endpoint. This flaw arises from missing authentication controls, enabling remote attackers to perform unauthorized file operations, which could lead to data loss, system compromise, or further exploitation of the affected environment.

CrowdSec has been tracking this vulnerability and its exploits since 15th of June 2026.

According to CrowdSec data, while opportunistic exploitation dominates, a portion of threat actors trying to exploit CVE-2026-20253 apply basic targeting methods such as port or service detection. This indicates emerging patterns of selective targeting.
Additionally, according to week-over-week analysis by CrowdSec, exploitation of CVE-2026-20253 is surging. Attack volumes are spiking well above historical norms, indicating widespread and escalating interest from threat actors. CVE-2026-20253 is currently experiencing high visibility and active exploitation across the internet.

Attackers exploit the Splunk PostgreSQL Sidecar Service by sending POST requests to endpoints matching `/splunkd/__raw/v1/postgres/recovery/backup`, often with a Basic Authorization header, to attempt unauthorized access or trigger error-based detection artifacts.

## Timeline

- 2026-06-10: CVE Published. CVE-2026-20253 is published to NVD.
- 2026-06-15: Rule Released. CrowdSec releases a rule to detect CVE-2026-20253 exploitation attempts against the CrowdSec Network.
- 2026-06-17: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2026-20253 for the first time.
- 2026-06-18: CISA KEV. CVE-2026-20253 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2026-06-21: CISA Remediation Deadline. Expiration of the CISA remediation deadline as described in [BOD 22-01](https://www.cisa.gov/news-events/directives/bod-22-01-reducing-significant-risk-known-exploited-vulnerabilities).

## References

- https://advisory.splunk.com/advisories/SVD-2026-0603
- https://github.com/watchtowrlabs/watchTowr-vs-Splunk-CVE-2026-20253/blob/main/watchTowr-vs-Splunk-CVE-2026-20253.py

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2026-20253) follows observed exploitation activity for CVE-2026-20253. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.