{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-20256","assignerOrgId":"d1c1063e-7a18-46af-9102-31f8928bc633","state":"PUBLISHED","assignerShortName":"cisco","dateReserved":"2025-10-08T11:59:15.401Z","datePublished":"2026-06-10T17:15:55.966Z","dateUpdated":"2026-06-10T18:19:26.044Z"},"containers":{"cna":{"affected":[{"product":"Splunk Enterprise","vendor":"Splunk","versions":[{"version":"10.2","status":"affected","versionType":"custom","lessThan":"10.2.4"},{"version":"10.0","status":"affected","versionType":"custom","lessThan":"10.0.7"},{"version":"9.4","status":"affected","versionType":"custom","lessThan":"9.4.12"},{"version":"9.3","status":"affected","versionType":"custom","lessThan":"9.3.13"}]},{"product":"Splunk Cloud Platform","vendor":"Splunk","versions":[{"version":"10.3.2512","status":"affected","versionType":"custom","lessThan":"10.3.2512.13"},{"version":"10.2.2510","status":"affected","versionType":"custom","lessThan":"10.2.2510.15"},{"version":"10.1.2507","status":"affected","versionType":"custom","lessThan":"10.1.2507.23"},{"version":"9.3.2411","status":"affected","versionType":"custom","lessThan":"9.3.2411.132"}]}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"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."}],"value":"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."}],"references":[{"url":"https://advisory.splunk.com/advisories/SVD-2026-0606"}],"title":"Improper Input Validation through Protocol-Relative URL in Classic Dashboards in Splunk Enterprise","datePublic":"2026-06-10T00:00:00.000Z","metrics":[{"cvssV3_1":{"vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","version":"3.1","baseScore":5.7,"baseSeverity":"MEDIUM"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"lang":"en","type":"cwe","description":"The product does not validate or incorrectly validates input that can affect the control flow or data flow of a program.","cweId":"CWE-20"}]}],"source":{"advisory":"SVD-2026-0606"},"credits":[{"lang":"en","value":"Tony Tong (tongster)"}],"providerMetadata":{"orgId":"d1c1063e-7a18-46af-9102-31f8928bc633","shortName":"cisco","dateUpdated":"2026-06-10T17:15:55.966Z"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-10T18:18:59.939227Z","id":"CVE-2026-20256","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-10T18:19:26.044Z"}}]}}