CVE-2026-20256
5.7 · MEDIUMOverview
CVE-2026-20256 is a medium-severity vulnerability affecting splunk splunk. It was published on June 10, 2026 and has a CVSS 3.1 base score of 5.7 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.7, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from splunk. Update splunk to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| splunk | splunk | >= 9.3.0, < 9.3.13 | Affected |
| splunk | splunk_cloud_platform | >= 9.3.2411, < 9.3.2411.132 | Affected |
Frequently Asked Questions
What is CVE-2026-20256?
CVE-2026-20256 is a medium-severity vulnerability affecting splunk splunk. It was published on June 10, 2026 and has a CVSS 3.1 base score of 5.7 (MEDIUM).
How severe is CVE-2026-20256?
This vulnerability has a CVSS 3.1 base score of 5.7, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-20256?
Check the references section for vendor advisories and patches from splunk. Update splunk to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-20256?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-20256 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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