CVE-2025-11065: Github.com/go viper/mapstructure/v2 Go-viper's Mapstructure May Leak Sensitive Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-2464-8j7c-4cjm",
  "modified" : "2026-01-27T21:01:22Z",
  "published" : "2025-08-21T14:37:19Z",
  "aliases" : [ "CVE-2025-11065" ],
  "summary" : "go-viper's mapstructure May Leak Sensitive Information in Logs When Processing Malformed Data",
  "details" : "### Summary\n\nUse of this library in a security-critical context may result in leaking sensitive information, if used to process sensitive fields.\n\n### Details\n\nOpenBao (and presumably HashiCorp Vault) have surfaced error messages from `mapstructure` as follows:\n\nhttps://github.com/openbao/openbao/blob/98c3a59c040efca724353ca46ca79bd5cdbab920/sdk/framework/field_data.go#L43-L50\n\n```go\n\t\t\t_, _, err := d.getPrimitive(field, schema)\n\t\t\tif err != nil {\n\t\t\t\treturn fmt.Errorf(\"error converting input for field %q: %w\", field, err)\n\t\t\t}\n```\n\nwhere this calls `mapstructure.WeakDecode(...)`: https://github.com/openbao/openbao/blob/98c3a59c040efca724353ca46ca79bd5cdbab920/sdk/framework/field_data.go#L181-L193\n\n```go\n\nfunc (d *FieldData) getPrimitive(k string, schema *FieldSchema) (interface{}, bool, error) {\n\traw, ok := d.Raw[k]\n\tif !ok {\n\t\treturn nil, false, nil\n\t}\n\n\tswitch t := schema.Type; t {\n\tcase TypeBool:\n\t\tvar result bool\n\t\tif err := mapstructure.WeakDecode(raw, &result); err != nil {\n\t\t\treturn nil, false, err\n\t\t}\n\t\treturn result, true, nil\n```\n\nNotably, `WeakDecode(...)` eventually calls one of the decode helpers, which surfaces the original value via `strconv` helpers:\n\nhttps://github.com/go-viper/mapstructure/blob/8c61ec1924fcfa522f9fc6b4618c672db61d1a38/mapstructure.go#L720-L727\n\nhttps://github.com/go-viper/mapstructure/blob/8c61ec1924fcfa522f9fc6b4618c672db61d1a38/mapstructure.go#L791-L798\n\nhttps://github.com/go-viper/mapstructure/blob/8c61ec1924fcfa522f9fc6b4618c672db61d1a38/decode_hooks.go#L180\n\n& more. These are different code paths than are fixed in the previous iteration at https://github.com/go-viper/mapstructure/security/advisories/GHSA-fv92-fjc5-jj9h.\n\n### PoC\n\nTo reproduce with OpenBao:\n\n```\n$ podman run --pull=always -p 8300:8300 openbao/openbao:latest server -dev -dev-root-token-id=root -dev-listen-address=0.0.0.0:8300\n```\n\nand in a new tab:\n\n```\n$ BAO_TOKEN=root BAO_ADDR=http://localhost:8300 bao auth enable userpass\nSuccess! Enabled userpass auth method at: userpass/\n$ curl -X PUT -H \"X-Vault-Request: true\" -H \"X-Vault-Token: root\" -d '{\"ttl\":\"asdf\"}' \"http://localhost:8200/v1/auth/userpass/users/asdf\"\n\n--> server logs:\n\n2025-06-25T21:32:25.101-0500 [ERROR] core: failed to run existence check: error=\"error converting input for field \\\"ttl\\\": time: invalid duration \\\"asdf\\\"\"\n```\n\n### Impact\n\nThis is an information disclosure bug with little mitigation. See https://discuss.hashicorp.com/t/hcsec-2025-09-vault-may-expose-sensitive-information-in-error-logs-when-processing-malformed-data-with-the-kv-v2-plugin/74717 for a previous version. That version was fixed, but this is in the second part of that error message (starting at `'' expected a map, got 'string'` -- when the field type is `string` and a `map` is provided, we see the above information leak -- the previous example had a `map` type field with a `string` value provided).\n\nThis was rated 4.5 Medium by HashiCorp in the past iteration.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/go-viper/mapstructure/v2"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.4.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.3.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/go-viper/mapstructure/security/advisories/GHSA-2464-8j7c-4cjm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-11065"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-viper/mapstructure/commit/742921c9ba2854d27baa64272487fc5075d2c39c"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/security/cve/CVE-2025-11065"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2391829"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/go-viper/mapstructure"
  }, {
    "type" : "WEB",
    "url" : "https://pkg.go.dev/vuln/GO-2025-3900"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-117" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-08-21T14:37:19Z",
    "nvd_published_at" : null
  }
}