GHSA-2464-8J7C-4CJM
Vulnerability from github – Published: 2025-08-21 14:37 – Updated: 2026-01-27 21:01Summary
Use of this library in a security-critical context may result in leaking sensitive information, if used to process sensitive fields.
Details
OpenBao (and presumably HashiCorp Vault) have surfaced error messages from mapstructure as follows:
https://github.com/openbao/openbao/blob/98c3a59c040efca724353ca46ca79bd5cdbab920/sdk/framework/field_data.go#L43-L50
_, _, err := d.getPrimitive(field, schema)
if err != nil {
return fmt.Errorf("error converting input for field %q: %w", field, err)
}
where this calls mapstructure.WeakDecode(...): https://github.com/openbao/openbao/blob/98c3a59c040efca724353ca46ca79bd5cdbab920/sdk/framework/field_data.go#L181-L193
func (d *FieldData) getPrimitive(k string, schema *FieldSchema) (interface{}, bool, error) {
raw, ok := d.Raw[k]
if !ok {
return nil, false, nil
}
switch t := schema.Type; t {
case TypeBool:
var result bool
if err := mapstructure.WeakDecode(raw, &result); err != nil {
return nil, false, err
}
return result, true, nil
Notably, WeakDecode(...) eventually calls one of the decode helpers, which surfaces the original value via strconv helpers:
https://github.com/go-viper/mapstructure/blob/8c61ec1924fcfa522f9fc6b4618c672db61d1a38/mapstructure.go#L720-L727
https://github.com/go-viper/mapstructure/blob/8c61ec1924fcfa522f9fc6b4618c672db61d1a38/mapstructure.go#L791-L798
https://github.com/go-viper/mapstructure/blob/8c61ec1924fcfa522f9fc6b4618c672db61d1a38/decode_hooks.go#L180
& 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.
PoC
To reproduce with OpenBao:
$ 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
and in a new tab:
$ BAO_TOKEN=root BAO_ADDR=http://localhost:8300 bao auth enable userpass
Success! Enabled userpass auth method at: userpass/
$ curl -X PUT -H "X-Vault-Request: true" -H "X-Vault-Token: root" -d '{"ttl":"asdf"}' "http://localhost:8200/v1/auth/userpass/users/asdf"
--> server logs:
2025-06-25T21:32:25.101-0500 [ERROR] core: failed to run existence check: error="error converting input for field \"ttl\": time: invalid duration \"asdf\""
Impact
This 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).
This was rated 4.5 Medium by HashiCorp in the past iteration.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2.3.0"
},
"package": {
"ecosystem": "Go",
"name": "github.com/go-viper/mapstructure/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.4.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-11065"
],
"database_specific": {
"cwe_ids": [
"CWE-117"
],
"github_reviewed": true,
"github_reviewed_at": "2025-08-21T14:37:19Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"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, \u0026result); 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\u0026 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 \u0027{\"ttl\":\"asdf\"}\u0027 \"http://localhost:8200/v1/auth/userpass/users/asdf\"\n\n--\u003e 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 `\u0027\u0027 expected a map, got \u0027string\u0027` -- 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.",
"id": "GHSA-2464-8j7c-4cjm",
"modified": "2026-01-27T21:01:22Z",
"published": "2025-08-21T14:37:19Z",
"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"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "go-viper\u0027s mapstructure May Leak Sensitive Information in Logs When Processing Malformed Data"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.