CVE-2026-20256
Description
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.
How to fix
- splunk splunk9.3.13, 9.4.12, 10.0.7, 10.2.4 or later
- splunk splunk_cloud_platform9.3.2411.132, 10.1.2507.23, 10.2.2510.15, 10.3.2512.13 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| splunk splunk | 9.3.0 ≤ v < 9.3.13, 9.4.0 ≤ v < 9.4.12, 10.0.0 ≤ v < 10.0.7, 10.2.0 ≤ v < 10.2.4 | 9.3.13, 9.4.12, 10.0.7, 10.2.4 |
| splunk splunk_cloud_platform | 9.3.2411 ≤ v < 9.3.2411.132, 10.1.2507 ≤ v < 10.1.2507.23, 10.2.2510 ≤ v < 10.2.2510.15, 10.3.2512 ≤ v < 10.3.2512.13 | 9.3.2411.132, 10.1.2507.23, 10.2.2510.15, 10.3.2512.13 |
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Attack Surface Management
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