Process Compose: Browser DNS rebinding lets websites control local process-compose MCP tools

{
  "id": "ad107960f3b09592cfe595b105d4ade4b664e916e5c07e0d16d1aaccb6eaca98",
  "url": "https://osv.dev/vulnerability/CVE-2026-77339",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Process Compose: Browser DNS rebinding lets websites control local process-compose MCP tools",
    "summary": "Process Compose is a scheduler and orchestrator for non-containerized applications. Prior to 1.120.0, the MCP SSE listener in src/mcp/server.go accepts browser-origin requests to /sse and the returned message endpoint without validating the Host header, validating the Origin header, or authenticating the caller. When MCP SSE is enabled, a malicious website can use DNS rebinding to reach the loopback listener and issue MCP requests. If expose_control_tools is enabled, the attacker can enumerate process state, read or search logs, truncate logs, and start, stop, restart, or scale local processes; configured user-defined tools can expose additional commands and output. The Gin REST API token middleware does not protect this separately started MCP listener. This issue is fixed in version 1.120.0.",
    "evidence": "osv:CVE-2026-77339",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-77339",
      "aliases": [
        "CVE-2026-77339",
        "GHSA-5gm3-9crp-6g3v",
        "GO-2026-6515"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:H/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/f1bonacc1/process-compose",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "0f3a8e6868f592f044a2ecd9387ff3025825ad46"
                },
                {
                  "fixed": "6ffa74f462cd2fa4f8dc1ee63c70b793b298c858"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.120.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "6ffa74f462cd2fa4f8dc1ee63c70b793b298c858"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "0f3a8e6868f592f044a2ecd9387ff3025825ad46"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v1.120.0"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.116.0",
            "v1.110.0",
            "v1.103.0",
            "v1.100.0",
            "v1.94.0",
            "v1.90.0",
            "v1.87.0",
            "v1.85.0",
            "v1.78.0",
            "v1.76.1",
            "v1.76.0",
            "v1.75.2",
            "v1.75.0",
            "v1.73.0",
            "v1.64.1",
            "v1.63.0",
            "v1.46.0",
            "v1.40.1",
            "v1.34.0",
            "v1.27.0",
            "v1.24.2",
            "v1.24.0",
            "v1.18.0",
            "v1.9.0",
            "v1.6.1",
            "v1.5.0",
            "v1.2.0",
            "v1.0.1",
            "v1.0.0",
            "v0.88.0",
            "v0.85.0",
            "v0.81.4",
            "v0.80.0",
            "v0.77.8",
            "v0.77.4",
            "v0.75.1",
            "v0.75.0",
            "v0.69.0",
            "v0.65.1",
            "v0.60.0",
            "v0.51.4",
            "v0.51.0",
            "v0.45.0",
            "v0.43.1",
            "v0.40.2",
            "v0.40.1",
            "v0.40.0",
            "v0.29.7",
            "v0.29.5",
            "v0.29.4",
            "v0.29.1",
            "v0.29.0",
            "v0.28.0",
            "v0.24.1",
            "v0.24.0",
            "v0.21.0",
            "v0.20.0",
            "v0.17.0",
            "v0.16.0",
            "v0.15.0",
            "v0.10.2",
            "v0.10.1",
            "v0.8.0",
            "v0.6.0",
            "v0.5.2",
            "v0.4.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77339.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:36.806247931Z",
      "provider": "osv",
      "references": [
        "https://github.com/F1bonacc1/process-compose/releases/tag/v1.120.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77339.json",
        "https://github.com/F1bonacc1/process-compose/security/advisories/GHSA-5gm3-9crp-6g3v",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-77339",
        "https://github.com/F1bonacc1/process-compose/commit/6ffa74f462cd2fa4f8dc1ee63c70b793b298c858"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-306",
          "CWE-346"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77339.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-77339",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504301,
  "published_at": "2026-09-18T16:37:19.072+00:00"
}