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.

CVSS v3 5.7 MEDIUM

5.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.1 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://advisory.splunk.com/advisories/SVD-2026-0606	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:splunk:splunk:::::enterprise:::*
	cpe:2.3:a:splunk:splunk:::::enterprise:::*
	cpe:2.3:a:splunk:splunk:::::enterprise:::*
	cpe:2.3:a:splunk:splunk:::::enterprise:::*

Configuration 2 (hide)

OR	cpe:2.3:a:splunk:splunk_cloud_platform::::::::
	cpe:2.3:a:splunk:splunk_cloud_platform::::::::
	cpe:2.3:a:splunk:splunk_cloud_platform::::::::
	cpe:2.3:a:splunk:splunk_cloud_platform::::::::

History

No history.

Information

Published : 2026-06-10 18:16

Updated : 2026-06-17 10:17

NVD link : CVE-2026-20256

Mitre link : CVE-2026-20256

CVE.ORG link : CVE-2026-20256

JSON object : View

Products Affected

splunk

splunk_cloud_platform
splunk

CWE

CWE-20

Improper Input Validation

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