CVE-2026-55176 (GCVE-0-2026-55176)

Vulnerability from cvelistv5 – Published: 2026-09-30 16:30 – Updated: 2026-09-30 16:30
VLAI
Title
Soft Machine: Cross-tenant workspace API auth bypass via shared `CONTAINER_SHARED_SECRET` bearer token
Summary
Soft Machine is a Virtual Machine–based agentic development environment / Cloud OS. In versions 0.2.247 and prior, two authentication helpers in /app/server.js — verifyContainerAuth() and authenticateWorkspaceHttp() — accept the global CONTAINER_SHARED_SECRET as a bearer token without verifying which workspace the caller belongs to. Because that secret is set identically on every container in the Fly app and is reachable from the user-facing process environment inside each workspace, any tenant can use it to authenticate to any other tenant's workspace API. The result is cross-workspace read, write, and destructive-restore primitives reachable from any paying customer's shell. The existing per-workspace token check (workspaceTokenMatches) protects the user-facing per-workspace token path, but the shared-secret bearer path bypasses it entirely. At time of publication, there are no publicly known patches.
Severity
9 (Critical)
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
Soft-Machine-io security Affected: <= 0.2.247
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{
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      "affected": [
        {
          "product": "security",
          "vendor": "Soft-Machine-io",
          "versions": [
            {
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              "version": "\u003c= 0.2.247"
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          "value": "Soft Machine is a Virtual Machine\u2013based agentic development environment / Cloud OS. In versions 0.2.247 and prior, two authentication helpers in /app/server.js \u2014 verifyContainerAuth() and authenticateWorkspaceHttp() \u2014 accept the global CONTAINER_SHARED_SECRET as a bearer token without verifying which workspace the caller belongs to. Because that secret is set identically on every container in the Fly app and is reachable from the user-facing process environment inside each workspace, any tenant can use it to authenticate to any other tenant\u0027s workspace API. The result is cross-workspace read, write, and destructive-restore primitives reachable from any paying customer\u0027s shell. The existing per-workspace token check (workspaceTokenMatches) protects the user-facing per-workspace token path, but the shared-secret bearer path bypasses it entirely. At time of publication, there are no publicly known patches."
        }
      ],
      "metrics": [
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            "attackVector": "ADJACENT_NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
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      "problemTypes": [
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          "descriptions": [
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        "discovery": "UNKNOWN"
      },
      "title": "Soft Machine: Cross-tenant workspace API auth bypass via shared `CONTAINER_SHARED_SECRET` bearer token"
    }
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  "cveMetadata": {
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    "cveId": "CVE-2026-55176",
    "datePublished": "2026-09-30T16:30:42.729Z",
    "dateReserved": "2026-06-16T15:20:43.085Z",
    "dateUpdated": "2026-09-30T16:30:42.729Z",
    "state": "PUBLISHED"
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        "cveTags": [],
        "descriptions": [
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            "lang": "en",
            "value": "Soft Machine is a Virtual Machine\u2013based agentic development environment / Cloud OS. In versions 0.2.247 and prior, two authentication helpers in /app/server.js \u2014 verifyContainerAuth() and authenticateWorkspaceHttp() \u2014 accept the global CONTAINER_SHARED_SECRET as a bearer token without verifying which workspace the caller belongs to. Because that secret is set identically on every container in the Fly app and is reachable from the user-facing process environment inside each workspace, any tenant can use it to authenticate to any other tenant\u0027s workspace API. The result is cross-workspace read, write, and destructive-restore primitives reachable from any paying customer\u0027s shell. The existing per-workspace token check (workspaceTokenMatches) protects the user-facing per-workspace token path, but the shared-secret bearer path bypasses it entirely. At time of publication, there are no publicly known patches."
          }
        ],
        "id": "CVE-2026-55176",
        "lastModified": "2026-09-30T19:57:08.043",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "ADJACENT_NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 9.0,
                "baseSeverity": "CRITICAL",
                "confidentialityImpact": "HIGH",
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    }
  }
}



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