BREW-MCP-ATLASSIAN-CVE-2… (CVE-2026-77260)

Vulnerability from osv_homebrew – Published: 2026-10-05 19:49 – Updated: 2026-10-05 19:49 – Source website
VLAI
Summary
MCP Atlassian: Arbitrary local file READ via unconstrained file_path in upload_attachment (Confluence + Jira)
Details

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the Confluence and Jira upload_attachment implementations accept an unconstrained file_path and open the referenced server-local file. A permitted MCP caller can upload sensitive host files to an Atlassian destination and then retrieve their contents. The advisory traces the vulnerable input and processing flow through upload_attachment, file_path, and CVE-2026-27825, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

Severity
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "upstream_fixed_in": "0.22.0"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "mcp-atlassian",
        "purl": "pkg:brew/mcp-atlassian"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.11.9"
            },
            {
              "fixed": "0.22.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "git",
    "upstream_evidence": [
      {
        "ecosystem": "GIT",
        "key": "https://github.com/sooperset/mcp-atlassian",
        "name": "https://github.com/sooperset/mcp-atlassian",
        "strategy": "git",
        "subject_version": "0.23.1"
      },
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/mcp-atlassian@0.23.1",
        "name": "mcp-atlassian",
        "strategy": "registry",
        "subject_version": "0.23.1"
      }
    ]
  },
  "details": "MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the Confluence and Jira upload_attachment implementations accept an unconstrained file_path and open the referenced server-local file. A permitted MCP caller can upload sensitive host files to an Atlassian destination and then retrieve their contents. The advisory traces the vulnerable input and processing flow through upload_attachment, file_path, and CVE-2026-27825, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.",
  "id": "BREW-mcp-atlassian-CVE-2026-77260",
  "modified": "2026-10-05T19:49:39Z",
  "published": "2026-10-05T19:49:39Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77260.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-f4p7-qx46-wc5j"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77260"
    },
    {
      "type": "FIX",
      "url": "https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460"
    },
    {
      "type": "FIX",
      "url": "https://github.com/sooperset/mcp-atlassian/pull/1448"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "MCP Atlassian: Arbitrary local file READ via unconstrained file_path in upload_attachment (Confluence + Jira)",
  "upstream": [
    "CVE-2026-77260",
    "GHSA-f4p7-qx46-wc5j",
    "PYSEC-2026-4091"
  ]
}



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