CVE-2025-25017: Elastic Kibana XSS Vulnerability

CVE-2025-25017 Overview

CVE-2025-25017 is a Cross-Site Scripting (XSS) vulnerability in Elastic Kibana. The flaw stems from improper neutralization of user-controlled input during web page generation [CWE-79]. An attacker can craft input that Kibana renders in the browser, executing arbitrary JavaScript in the context of an authenticated user session.

Elastic addressed the issue in Kibana 8.18.8, 8.19.4, 9.0.7, and 9.1.4. Successful exploitation requires user interaction and can result in session compromise, unauthorized actions within Kibana, or exfiltration of data visible to the victim user.

Critical Impact
Attackers can execute arbitrary JavaScript in a victim's browser session, enabling theft of session data and unauthorized actions within Kibana dashboards.

Affected Products

Elastic Kibana versions prior to 8.18.8
Elastic Kibana 8.19.x prior to 8.19.4
Elastic Kibana 9.0.x prior to 9.0.7 and 9.1.x prior to 9.1.4

Discovery Timeline

2025-10-10 - CVE-2025-25017 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-25017

Vulnerability Analysis

The vulnerability resides in Kibana's web page generation logic, where user-supplied input is written to the response without sufficient encoding or sanitization. When a victim loads the affected view, the browser interprets the injected payload as executable script rather than data.

Because Kibana runs authenticated sessions to Elasticsearch, script execution in the victim's browser grants the attacker the same effective privileges as the logged-in user. This includes viewing indices, running queries, and interacting with Kibana APIs from the victim's context.

The attack targets confidentiality and integrity of data rendered in the user interface. Availability is not directly impacted, and the scope changes because injected script executes across security boundaries within the browser.

Root Cause

The root cause is missing output encoding in a Kibana rendering path [CWE-79]. Content originating from an attacker-controllable source flows into HTML output without contextual escaping, allowing HTML or JavaScript tokens to break out of the intended data context.

Attack Vector

An attacker crafts a malicious URL or injects payload content into a Kibana object that another user will view. The victim must interact with the resource, such as clicking a link or opening a shared dashboard. Once rendered, the payload executes in the victim's browser under the Kibana origin.

Elastic has not published a public proof-of-concept. See the Elastic Kibana Security Update for vendor guidance and version-specific technical details.

Detection Methods for CVE-2025-25017

Indicators of Compromise

Unexpected outbound HTTP requests from browsers hosting active Kibana sessions to attacker-controlled domains
Kibana access logs containing URL parameters with <script>, javascript:, onerror=, or encoded variants such as %3Cscript%3E
Creation or modification of Kibana saved objects containing HTML tags or JavaScript syntax in text fields

Detection Strategies

Inspect Kibana HTTP access logs for query strings and POST bodies containing HTML control characters and event-handler attributes
Deploy a Content Security Policy (CSP) in report-only mode to surface inline script execution attempts against Kibana origins
Correlate authenticated Kibana sessions with anomalous API calls originating shortly after a user clicks an externally shared link

Monitoring Recommendations

Enable Kibana audit logging and forward events to a centralized analytics platform for review of saved-object writes and dashboard sharing activity
Alert on Kibana user sessions that suddenly enumerate indices or export data outside of established baselines
Track browser telemetry for script errors and CSP violations originating from Kibana hostnames

How to Mitigate CVE-2025-25017

Immediate Actions Required

Upgrade Kibana to 8.18.8, 8.19.4, 9.0.7, or 9.1.4 as applicable to your deployment branch
Invalidate active Kibana sessions after patching to force reauthentication and clear any cached malicious content
Review recently created or modified Kibana saved objects, dashboards, and visualizations for suspicious HTML or script content

Patch Information

Elastic released fixed versions of Kibana that address the improper input neutralization. Refer to the Elastic Kibana Security Update ESA-2025-16 for the full advisory and upgrade instructions.

Workarounds

Restrict Kibana network exposure to trusted users through VPN, reverse proxy authentication, or IP allowlisting until patches are applied
Enforce a strict Content Security Policy that blocks inline script execution and restricts allowed script sources for the Kibana origin
Educate users to avoid clicking Kibana links received from untrusted sources or shared through external channels

bash

# Verify installed Kibana version and confirm patched build
curl -sk -u "$KIBANA_USER:$KIBANA_PASS" \
  "https://kibana.example.com:5601/api/status" \
  | jq '.version.number'

# Expected patched versions: 8.18.8, 8.19.4, 9.0.7, or 9.1.4