Improper Input Validation of Native Splunk Usernames through the REST API in Splunk Enterprise

{
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  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-76277",
    "assignerOrgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
    "assignerShortName": "cisco",
    "dateUpdated": "2026-10-08T15:06:09.743Z",
    "dateReserved": "2026-08-19T12:02:03.621Z",
    "datePublished": "2026-10-07T20:46:35.907Z",
    "state": "PUBLISHED"
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        "dateUpdated": "2026-10-07T20:46:35.907Z"
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      "datePublic": "2026-10-07T00:00:00.000Z",
      "title": "Improper Input Validation of Native Splunk Usernames through the REST API in Splunk Enterprise",
      "descriptions": [
        {
          "lang": "en",
          "value": "In Splunk Enterprise versions below 10.4.3, 10.2.7, 10.0.10, and 9.4.15, a user that holds a role with the edit_user capability could create a native Splunk username that ends with a period. The vulnerability is possible because username validation does not reject a trailing period before the username is used for a user directory. This can cause distinct native Splunk usernames to share per-user configuration data, and user-management operations can affect the wrong account or fail. For more information see Set up native Splunk authentication (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/use-the-native-splunk-platform-authentication-scheme/set-up-native-splunk-authentication) and Define roles on the Splunk platform with capabilities (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities) in the Splunk documentation.",
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              "value": "In Splunk Enterprise versions below 10.4.3, 10.2.7, 10.0.10, and 9.4.15, a user that holds a role with the `edit_user` capability could create a native Splunk username that ends with a period. The vulnerability is possible because username validation does not reject a trailing period before the username is used for a user directory. This can cause distinct native Splunk usernames to share per-user configuration data, and user-management operations can affect the wrong account or fail. For more information see [Set up native Splunk authentication](https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/use-the-native-splunk-platform-authentication-scheme/set-up-native-splunk-authentication) and [Define roles on the Splunk platform with capabilities](https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities) in the Splunk documentation."
            }
          ]
        }
      ],
      "affected": [
        {
          "vendor": "Splunk",
          "product": "Splunk Enterprise",
          "modules": [
            "REST API"
          ],
          "versions": [
            {
              "version": "10.4",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "10.4.3"
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            {
              "version": "10.2",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "10.2.7"
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              "version": "10.0",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "10.0.10"
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            {
              "version": "9.4",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "9.4.15"
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          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "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",
              "type": "cwe"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://advisory.splunk.com/advisories/SVD-2026-1001"
        }
      ],
      "metrics": [
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          "format": "CVSS",
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              "lang": "en",
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            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L",
            "baseScore": 4.1,
            "baseSeverity": "MEDIUM"
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      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade Splunk Enterprise to versions 10.4.3, 10.2.7, 10.0.10, and 9.4.15, or higher."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Gabriel Nitu, Splunk",
          "type": "finder"
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