CVE-2026-20256
MediumCVSS 5.7Exploitation Probability (EPSS)
Low risk17th percentile - higher than 17% of all known CVEs
Summary
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user can cause data exfiltration through classic dashboards by redirecting a victim to an external site using a protocol-relative URL in a drill-down link.
Risk Assessment
The organization may be exposed to data leakage, which could lead to the loss of sensitive information and security breaches.
Recommendation
It is recommended to upgrade to the latest version of Splunk to mitigate this vulnerability and review access policies for low-privileged users.
Other vulnerabilities in Splunk Enterprise, Splunk Cloud Platform
See all- CVE-2026-20259Medium
In Splunk Enterprise versions below 10.2.4 and 10.0.7, and Splunk Cloud Platform versions below 10.4.2604.0, 10.3.2512.12, 10.2.2510.15, 10.1.2507.23, 10.0.2503.14, and 9.3.2411.131, a user with a role containing the high-privilege capability `edit_saved_search_owner` could reassign saved search ownership to users outside their authorized scope. The ownership reassignment endpoint lacks access control.
- CVE-2026-20258High
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.11, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user can store a malicious script in a classic dashboard HTML panel, leading to unauthorized JavaScript code execution in another user's browser.
- CVE-2026-20257Medium
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user can craft a classic dashboard that exfiltrates sensitive data from the browser of a higher-privileged user who views it. The issue arises from the lack of full validation of style attribute values in classic dashboard panels.
- CVE-2026-20255Medium
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user can craft a malicious classic dashboard that exfiltrates sensitive data to an external server.
- CVE-2026-20254Medium
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user can craft a malicious dashboard that exfiltrates sensitive data to an external server when a higher-privileged user views it, exploiting a validation flaw in the Trusted Domains security check.
- CVE-2026-20252High
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.4.2604.3, 10.3.2512.12, 10.2.2510.14, 10.1.2507.22, and 9.3.2411.132, a low-privileged user can send server-side requests to arbitrary internal destinations through the Dashboard Studio PDF export feature. The vulnerability exists due to improper trusted-domain validation and automatic following of HTTP redirects without re-validating each redirect target.
Original NVD description (English source)
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user that does not hold the 'admin' or 'power' Splunk roles could cause data exfiltration through classic dashboards by redirecting a victim to an external site using a protocol-relative URL in a drill-down link.<br><br>The vulnerability exists because the URL classifier in classic dashboards only recognizes `http://` and `https://` schemes when checking for external URLs. Protocol-relative URLs such as `//attacker.com` bypass this check entirely, and Splunk Web does not show the external-navigation warning dialog to the victim.