What’s Vulnerable › Vulnerabilities
CVE-2026-19202: Token Cache Reuse in mcp-toolbox-sdk-python
- Severity: critical (CVSS 9.1 v4.0)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-22 · updated 2026-09-23
- Weakness: CWE-524
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.
Affected products
- Google mcp-toolbox-sdk-python: through 1.1.0
References
Get alerted when CVE-2026-19202 or the next vulnerability affects your stack