{"id":"CVE-2026-20256","aliases":["EUVD-2026-36080","GHSA-p326-4xf8-xp88"],"status":"published","title":"Improper Input Validation through Protocol-Relative URL in Classic Dashboards in Splunk Enterprise","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.\u003cbr\u003e\u003cbr\u003eThe 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.","severity":{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00361,"percentile":0.30181,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-20"],"published":"2026-06-10T17:15:55Z","modified":"2026-06-17T10:17:20Z","products":[{"vendor":"splunk","product":"splunk"},{"vendor":"splunk","product":"splunk cloud platform"},{"vendor":"splunk","product":"splunk enterprise"},{"vendor":"splunk","product":"splunk_cloud_platform"}],"references":[{"url":"https://advisory.splunk.com/advisories/SVD-2026-0606","tags":["Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20256"},{"url":"https://github.com/advisories/GHSA-p326-4xf8-xp88"}],"sources":{"cve":[{"id":"CVE-2026-20256","title":"Improper Input Validation through Protocol-Relative URL in Classic Dashboards in Splunk Enterprise","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.\u003cbr\u003e\u003cbr\u003eThe 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.","status":"published","published":"2026-06-10T17:15:55.966Z","modified":"2026-06-10T18:19:26.044Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T13:35:33.380441Z"}],"euvd":[{"id":"EUVD-2026-36080","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.\u003cbr\u003e\u003cbr\u003eThe 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.","status":"published","published":"2026-06-10T17:15:55Z","modified":"2026-06-10T18:19:26Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T18:20:44.937217Z"}],"ghsa":[{"id":"GHSA-p326-4xf8-xp88","title":"In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform...","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.\u003cbr\u003e\u003cbr\u003eThe 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.","status":"published","published":"2026-06-10T18:31:46Z","modified":"2026-06-10T18:31:53Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:08:43.963781Z"}],"nvd":[{"id":"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.\u003cbr\u003e\u003cbr\u003eThe 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.","status":"published","published":"2026-06-10T18:16:41.133Z","modified":"2026-06-17T10:17:20.563Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:12:23.485267Z"}]}}