---
id: CVE-2026-77271
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, validate_safe_path defaults its base
  directory to os.getcwd(), and affected Confluence attachment call sites omit
  base_…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-22
  - CWE-94
vendor: mcp-atlassian
product: mcp_atlassian
affected:
  - mcp_atlassian < 0.22.0
patched:
  - mcp_atlassian 0.22.0
published: '2026-09-22'
updated: '2026-09-28'
sourceUpdated: '2026-09-28T13:45:34.133'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77271'
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-6vmq-24h2-pj7j
    label: security-advisories@github.com
  - url: >-
      https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6vmq-24h2-pj7j
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77271'
  - url: 'https://github.com/advisories/GHSA-6vmq-24h2-pj7j'
  - url: 'https://github.com/sooperset/mcp-atlassian'
  - url: 'https://pypi.org/project/mcp-atlassian'
tags:
  - nvd
  - cve.org
  - exploit-available
  - ghsa
  - pip
  - osv
epss: 0.00596
epssPercentile: 0.4828
aliases:
  - GHSA-6vmq-24h2-pj7j
  - PYSEC-2026-4087
ecosystem: pip
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-24T14:27:52.995265Z'
scores:
  nvd: 8.8
  cna: 8.3
ingestedAt: '2026-09-22T19:09:09.987Z'
---

## Overview

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_safe_path defaults its base directory to os.getcwd(), and affected Confluence attachment call sites omit base_dir, allowing attacker-selected writes within the working directory. This Python module overwrite can provide code execution when the application later imports the modified module, bypassing the remediation tracked as CVE-2026-27825. This issue is fixed in version 0.22.0.

## Affected

- `mcp_atlassian < 0.22.0`

## Remediation

Upgrade past the affected range:

- `mcp_atlassian 0.22.0`

## Package advisory (CVE-2026-77271)

Affected packages:

- `mcp-atlassian < 0.22.0`

Patched in:

- `mcp-atlassian 0.22.0`

Source: https://github.com/advisories/GHSA-6vmq-24h2-pj7j