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TI-2026-53942 Aliases CVE-2026-77258GHSA-93xw-j965-9mx3

MCP Atlassian: Arbitrary file read/exfiltration via upload_attachment missing validate_safe_path()

Priority HIGH 67CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-22 and the CVSS impact.

Summary

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, upload_attachment in src/mcp_atlassian/confluence/attachments.py accepts a caller-controlled file_path and opens the selected server-local file without restricting it to the workspace. A permitted Confluence MCP caller can upload the file as an attachment and disclose data readable by the server process. This issue is fixed in version 0.22.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00374 31st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed mcp-atlassian (sooperset): 0.22.0mcp-atlassian (PyPI): 0.22.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
soopersetmcp-atlassianbefore 0.22.00.22.0Patch availableCNA
—mcp-atlassian (PyPI)before 0.22.00.22.0Patch availableGHSA-93xw-j965-9mx3
  • mcp-atlassian Vendorsooperset Affected before 0.22.0 Fixed in 0.22.0 Patch available CNA
  • mcp-atlassian (PyPI) Vendor— Affected before 0.22.0 Fixed in 0.22.0 Patch available GHSA-93xw-j965-9mx3

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mcp-atlassian:mcp_atlassian:*:*:*:*:*:*:*:*before 0.22.0VulnerableMcp-atlassian
  • cpe:2.3:a:mcp-atlassian:mcp_atlassian:*:*:*:*:*:*:*:* Versions before 0.22.0 Vulnerable ·Mcp-atlassian

Remediation

  • Fix · CNA mcp-atlassian (sooperset) Fixed in 0.22.0
  • Fix · GHSA-93xw-j965-9mx3 mcp-atlassian (PyPI) Fixed in 0.22.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-77258
  2. 2026-10-03 Alias added: GHSA-93xw-j965-9mx3

References

Exploit 1

Patch 2

Advisory 1

Other 2

  • TI-2026-53938 MCP Atlassian: Unauthenticated HTTP MCP requests can use globally configured Jira and Confluence credentials CVSS 3.1CRITICAL 9.1
  • TI-2026-53957 MCP Atlassian: SSRF Protection Bypass CVSS 4.0HIGH 8.8
  • TI-2026-53935 Protection mechanism failure in sooperset mcp-atlassian CVSS 4.0HIGH 8.3
  • TI-2026-53946 Path traversal in sooperset mcp-atlassian CVSS 3.1HIGH 8.6
  • TI-2026-53932 Path traversal in sooperset mcp-atlassian CVSS 3.1HIGH 8.6
  • TI-2026-22177 Path traversal in sooperset mcp-atlassian CVSS 3.1CRITICAL 9.1
See all 33 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences