---
id: CVE-2026-77258
title: >-
  MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products
  (Confluence and Jira)
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 se…
severity: high
cvss: 7.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N'
cwe:
  - CWE-22
vendor: sooperset
product: mcp-atlassian
affected:
  - mcp-atlassian < 0.22.0
patched:
  - mcp-atlassian 0.22.0
published: '2026-09-22'
updated: '2026-09-26'
sourceUpdated: '2026-09-26T00:16:35.523'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77258'
references:
  - url: >-
      https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460
    label: security-advisories@github.com
  - url: 'https://github.com/sooperset/mcp-atlassian/pull/1448'
    label: security-advisories@github.com
  - url: 'https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-93xw-j965-9mx3
    label: security-advisories@github.com
  - url: >-
      https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-93xw-j965-9mx3
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77258'
  - url: 'https://github.com/advisories/GHSA-93xw-j965-9mx3'
  - url: 'https://github.com/sooperset/mcp-atlassian'
  - url: 'https://pypi.org/project/mcp-atlassian'
tags:
  - nvd
  - cve.org
  - exploit-available
  - ghsa
  - pip
  - osv
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-25T23:48:48.170129Z'
epss: 0.00374
epssPercentile: 0.31235
aliases:
  - GHSA-93xw-j965-9mx3
  - PYSEC-2026-4088
ecosystem: pip
ingestedAt: '2026-09-22T18:08:12.496Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-77258)

Affected packages:

- `mcp-atlassian < 0.22.0`

Patched in:

- `mcp-atlassian 0.22.0`

Source: https://github.com/advisories/GHSA-93xw-j965-9mx3