go-viper's mapstructure May Leak Sensitive Information in Logs When Processing Malformed Data

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.3 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS

• CVE-2025-11065: 0.43% estimated exploitation activity in the next 30 days; percentile 37.74 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary 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/fielddata.go#L43-L50 where this calls mapstructure.WeakDecode(...): https://github.com/openbao/openbao/blob/98c3a59c040efca724353ca46ca79bd5cdbab920/sdk/framework/fielddata.go#L181-L193 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/decodehooks.go#L180 & more.…

Published by the source

21 Aug 2025, 14:37 UTC

Last modified by the source

27 Jan 2026, 21:01 UTC

Source last checked

26 Oct 2026, 15:14 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-2464-8j7c-4cjm

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2025-11065

Advisory: go-viper's mapstructure May Leak Sensitive Information in Logs When Processing Malformed Data
IDs: CVE-2025-11065, GHSA-2464-8j7c-4cjm
Record: https://patchnext.com/advisories/cve-2025-11065 (revision 1, source checked 26 Oct 2026, 15:14 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/go-viper/mapstructure/v2 2.4.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/go-viper/mapstructure/v2: affected <= 2.3.0; fixed in 2.4.0

## Suggested inspection (read-only)
- Go github.com/go-viper/mapstructure/v2: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/go-viper/mapstructure/v2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-2464-8j7c-4cjm (GitHub-reviewed advisory GHSA-2464-8j7c-4cjm lists affected ranges: Go github.com/go-viper/mapstructure/v2 >=0 <=2.3.0)

Commands are suggestions: review each one before running it.