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TI-2026-15678 Aliases CVE-2026-19202GHSA-jcjp-gr26-563j

Token Cache Reuse in mcp-toolbox-sdk-python

Priority MEDIUM 47CWE-524Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00228 13th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Googlemcp-toolbox-sdk-pythonup to 1.1.0—No fix listedCNA
  • mcp-toolbox-sdk-python VendorGoogle Affected up to 1.1.0 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-19202
  2. 2026-10-03 Alias added: GHSA-jcjp-gr26-563j

References

Patch 1

  • TI-2025-09686 Type confusion in Google Chrome KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-07390 Type confusion in Google Chrome KEVCVSS 3.1CRITICAL 9.6
  • TI-2024-04898 Type confusion in Google Chrome KEVCVSS 3.1CRITICAL 9.6
  • TI-2024-04600 Type confusion in Google Chrome KEVCVSS 3.1CRITICAL 9.6
  • TI-2024-04346 Use after free in Google Chrome KEVCVSS 3.1CRITICAL 9.6
  • TI-2023-05824 Integer overflow in Google Chrome KEVCVSS 3.1CRITICAL 9.6
See all 17247 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences