CVE-2026-109799 PUBLISHED

Improper verification of JWT signature in IASContextProvider leads to tenant/user identity spoofing ( sap-cloud-sdk (pip))

Assigner: sap
Reserved: 13.10.2026 Published: 10.11.2026 Updated: 10.11.2026

The SAP Cloud SDK for Python contains an improper cryptographic signature verification vulnerability (CWE-347) in IASContextProvider, the runtime-context provider registered by default via bootstrap(app).IASContextProvider extracted the app_tid, sap_gtid and user_uuid claims from the IAS JWT in the Authorization header using an unverified decoder and wrote them into the request-scoped RuntimeContext without validating the token signature. A remote caller could submit a self-signed JWT naming a victim tenant/user; the forged identity then propagated to every consumer of the runtime context:OTel span attributes (sap.tenancy.tenant_id, user.id) via RuntimeContextSpanProcessorlog records via IdentityLogFilteraudit events (tenant_id, user_initiator_id) via AuditClienttenant routing via CBCClientThis completes an earlier remediation that fixed the same unverified pattern in StarletteIASTelemetryMiddleware but did not cover IASContextProvider.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS Score: 7.5

Product Status

Vendor SAP_SE
Product SAP Cloud SDK for Python
Versions Default: unaffected
  • Version < 0.63.1 is affected

References

Problem Types