CVE-2026-20256

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.

• splunk splunk (>= 9.3.0 < 9.3.13) • splunk splunk (>= 9.4.0 < 9.4.12) • splunk splunk (>= 10.0.0 < 10.0.7) • splunk splunk (>= 10.2.0 < 10.2.4) • splunk splunk cloud platform (>= 9.3.2411 < 9.3.2411.132) • splunk splunk cloud platform (>= 10.1.2507 < 10.1.2507.23) • splunk splunk cloud platform (>= 10.2.2510 < 10.2.2510.15) • splunk splunk cloud platform (>= 10.3.2512 < 10.3.2512.13)