CVE-2026-77253

MCP Atlassian: Jira and Confluence attachment upload tools can read arbitrary server-local files

Published: Sep 22, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-22

7.1HIGH

Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, Jira and Confluence attachment upload tools accept arbitrary local filesystem paths and send the selected bytes to Atlassian. In HTTP or multi-user deployments, a caller can cross the client-to-server filesystem boundary and disclose configuration, credentials, mounted secrets, or other files readable by the MCP process. The advisory traces the vulnerable input and processing flow through jira_upload_attachment, confluence_upload_attachment, file_path, and server-local filesystem, 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:UScope

Unchanged

Impact

C:HConfidentiality

High

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-22

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-vc25-24vv-fxxm

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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