Improper Authentication Affecting github.com/googleapis/mcp-toolbox/internal/server package, versions <1.4.0
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMGOOGLEAPISMCPTOOLBOXINTERNALSERVER-17707935
- published30 Jun 2026
- disclosed18 Jun 2026
- creditUnknown
Introduced: 18 Jun 2026
CVE-2026-11717 Â (opens in a new tab)How to fix?
Upgrade github.com/googleapis/mcp-toolbox/internal/server to version 1.4.0 or higher.
Overview
Affected versions of this package are vulnerable to Improper Authentication through the validateOpaqueToken process. An attacker can gain unauthorized access to protected tools and underlying data sources by submitting an OAuth 2.0 introspection response that omits the mandatory active field, causing the system to incorrectly accept invalid tokens.