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CVE-2026-109799

Full vulnerability record from the local CVENow database.

Description

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.

Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Received
Source identifier
Published
2026-11-10 01:17:13.887000
Last modified
2026-11-10 01:17:13.887000
View original CVE JSON
{
  "id": "CVE-2026-109799",
  "sourceIdentifier": "[email protected]",
  "published": "2026-11-10T01:17:13.887",
  "lastModified": "2026-11-10T01:17:13.887",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "SAP_SE",
          "product": "SAP Cloud SDK for Python",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "< 0.63.1",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/SAP/cloud-sdk-python/security/advisories/GHSA-93m8-crj2-v997",
      "source": "[email protected]"
    },
    {
      "url": "https://url.sap/sapsecuritypatchday",
      "source": "[email protected]"
    }
  ]
}