---
id: "CVE-2026-109799"
page: "https://infrastack.ai/live/CVE-2026-109799"
kind: "vulnerability"
aliases: ["CVE-2026-109799"]
title: "SAP Cloud SDK for Python: forged JWT sets tenant and user identity"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "sap-cloud-sdk", "fixed": ["0.63.1"], "affected": "< 0.63.1", "ecosystem": "pypi"}]
ecosystems: []
tags: ["ias", "multi-tenant", "package", "pip", "python", "sap-cloud-sdk"]
not_affected_if: ["no-ias-jwt", "upstream-token-validation"]
published_at: "2026-11-10T01:17:13+00:00"
first_seen_at: "2026-11-10T01:26:36+00:00"
updated_at: "2026-11-10T01:35:40+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-109799", "first_seen_at": "2026-11-10T01:26:36+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-11-10T01:35:40+00:00"}]
exploit_sources: []
---

# SAP Cloud SDK for Python: forged JWT sets tenant and user identity

Link for people: https://infrastack.ai/live/CVE-2026-109799 (this .md is for agents)

SAP Cloud SDK for Python (sap-cloud-sdk < 0.63.1) trusted tenant, tenant-group and user claims from the IAS JWT without checking its signature. A remote caller could send a self-signed token naming a victim tenant and user, and that forged identity flowed into telemetry, logs, audit events and tenant routing. Fixed in 0.63.1.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- pypi:sap-cloud-sdk affected < 0.63.1 fixed 0.63.1

## How to check

Run: pip show sap-cloud-sdk (or pip list). Versions below 0.63.1 are affected if the app calls bootstrap(app), which registers IASContextProvider by default, and accepts IAS JWTs in the Authorization header.

## Fix

Upgrade sap-cloud-sdk (pip) to 0.63.1 or later. 0.63.1 verifies the IAS JWT signature via JWKS-backed IASVerifier and returns an empty context if verification fails or no IAS binding exists.

## Timeline

- 2026-11-10T01:26:36+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-109799
- 2026-11-10T01:35:40+00:00 analyst — Read GHSA-93m8-crj2-v997 (SAP's own advisory): sap-cloud-sdk (pip) < 0.63.1 affected, 0.63.1 fixes via JWKS-backed IASVerifier, fail-closed. No exploitation/PoC seen; did not search social.

## Documents

- [advisory] Vendor advisory: github.com https://github.com/SAP/cloud-sdk-python/security/advisories/GHSA-93m8-crj2-v997

## From the sources

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.

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