CVE-2026-19202

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/googleapis/mcp-toolbox-sdk-python/pull/675

Configurations

No configuration.

History

22 Sep 2026, 22:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-22 22:17

Updated : 2026-09-23 19:42

NVD link : CVE-2026-19202

Mitre link : CVE-2026-19202

CVE.ORG link : CVE-2026-19202

JSON object : View

Products Affected

No product.

CWE

CWE-524

Use of Cache Containing Sensitive Information

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