Vulnerability Description
A caching flaw in the toolbox-core package of the mcp-toolbox-sdk-python SDK causes the same Google ID token to be cached and reused across different audiences. If an application uses the SDK to authenticate to two or more different audiences within the same process, the module-level token cache fails to key its cached tokens by the requested audience. Consequently, a valid, unexpired token minted for a sensitive service (Service A) can be retrieved from the cache and sent to a secondary service (Service B). An attacker who operates, compromises, or monitors traffic to Service B can capture this token and replay it to impersonate the victim application against Service A.
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-19202?
CVE-2026-19202 is a documented vulnerability. A caching flaw in the toolbox-core package of the mcp-toolbox-sdk-python SDK causes the same Google ID token to be cached and reused across different audiences. If an application uses the SDK to authe...
How severe is CVE-2026-19202?
CVSS scoring is not yet available for CVE-2026-19202. Check NVD for updates.
Is there a patch for CVE-2026-19202?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.