{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "1.8.1"
              },
              {
                "fixed": "1.73.0"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "65edb153bd37f322a45c6c928d757e4090ba3265"
            },
            {
              "fixed": "72573426f320fefc89a96ba55ce05c752d182123"
            }
          ],
          "repo": "https://github.com/eclipse-theia/theia",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-78g8-vm3p-97c6"
  ],
  "database_specific": {
    "cna_assigner": "eclipse",
    "cwe_ids": [
      "CWE-1385",
      "CWE-306"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10054.json"
  },
  "details": "In affected versions of Eclipse Theia (1.8.1 and later), the browser backend exposes privileged terminal RPC over WebSocket (/services/shell-terminal, /services/terminals/:id) without service-level authentication.\n\n\n\n\nWebSocket origin validation in @theia/core is fail-open: connections are accepted when the Origin header is missing or when no THEIA_HOSTS allowlist is configured (the default). The Socket.IO integration additionally replaces the real Origin header with a client-supplied fix-origin header that an attacker can control or omit.\n\n\n\n\nAs a result, a foreign-origin web page visited by a user with a running Theia instance can open the /services WebSocket namespace, invoke terminal creation, attach to the resulting terminal data channel, execute arbitrary OS commands, and read their output. This affects both local developer setups (drive-by attack) and hosted or tunneled deployments without strong external authentication.\n\n\n\n\nA fix is in development that enforces same-origin validation by default, removes trust in the fix-origin header, gates HTTP and WebSocket access on a SameSite=Strict; HttpOnly connection-token cookie, and sanitizes shell terminal creation options.",
  "id": "CVE-2026-10054",
  "modified": "2026-08-12T03:51:25.599255892Z",
  "published": "2026-07-03T10:11:32.446Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/376"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10054.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/eclipse-theia/theia/security/advisories/GHSA-78g8-vm3p-97c6"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-10054"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}