Improper Output Neutralization for Logs Affecting github.com/go-viper/mapstructure/v2 package, versions <2.4.0
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMGOVIPERMAPSTRUCTUREV2-12177854
- published26 Aug 2025
- disclosed21 Aug 2025
- creditAlexander Scheel
Introduced: 21 Aug 2025
New CVE NOT AVAILABLE CWE-117 (opens in a new tab)Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade github.com/go-viper/mapstructure/v2 to version 2.4.0 or higher.
Overview
Affected versions of this package are vulnerable to Improper Output Neutralization for Logs via the WeakDecode function when handling malformed input data. An attacker can cause sensitive information to be included in error logs by submitting specially crafted input that triggers error messages containing original values.