CVE-2026-77259

MCP Atlassian: Arbitrary file read via confluence_upload_attachment allows exfiltration of server credentials

Published: Sep 22, 2026Updated: Sep 26, 2026 Sources: CVE List NVDCWE-22

7.7HIGH

Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, confluence_upload_attachment opens a caller-selected server-local file without checking that the resolved path remains in the workspace. A caller can upload environment files, credentials, or other readable host data to a Confluence page and retrieve it through Atlassian. The advisory traces the vulnerable input and processing flow through confluence_upload_attachment, file_path, and open(file_path, "rb"), which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:NIntegrity

None

A:NAvailability

None

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Weaknesses

CWE-22 CWE-552

Affected Products

sooperset

commercialaka mcp atlassian

mcp-atlassianOn-prem

Enterprise Software / collaboration-groupware

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Collection

Discovery

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References

https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6cr4-ccf3-x7h4

github.com

https://github.com/sooperset/mcp-atlassian/pull/1448

github.com

https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460

github.com

and 1 more references View all →

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