---
id: CVE-2026-77246
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, an HTTP transport deployment with
  READ_ONLY_MODE=false accepts a request without an Authorization identity and
  permits …
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N'
cwe:
  - CWE-22
  - CWE-200
  - CWE-441
vendor: sooperset
product: mcp-atlassian
affected:
  - mcp-atlassian < 0.22.0
patched:
  - mcp-atlassian 0.22.0
published: '2026-09-22'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T16:17:10.677'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77246'
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-wv8v-v4c5-v75j
    label: security-advisories@github.com
  - url: >-
      https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wv8v-v4c5-v75j
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://github.com/advisories/GHSA-wv8v-v4c5-v75j'
  - url: 'https://github.com/sooperset/mcp-atlassian'
tags:
  - nvd
  - cve.org
  - ghsa
  - pip
  - osv
  - exploit-available
epss: 0.00218
epssPercentile: 0.10801
aliases:
  - GHSA-wv8v-v4c5-v75j
ecosystem: pip
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-24T15:26:25.494462Z'
ingestedAt: '2026-09-22T19:09:09.999Z'
---

## Overview

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, an HTTP transport deployment with READ_ONLY_MODE=false accepts a request without an Authorization identity and permits attacker-controlled Atlassian service headers, including X-Atlassian-Confluence-Url, to select a public attacker hostname or one allowed by MCP_ALLOWED_URL_DOMAINS. A caller can then invoke confluence_upload_attachment or the Jira attachment variant in src/mcp_atlassian/jira/attachments.py with a server-local file_path and cause the MCP process to send the file to the selected attachment endpoint. 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-2026-77246)

Affected packages:

- `mcp-atlassian < 0.22.0`

Patched in:

- `mcp-atlassian 0.22.0`

Source: https://github.com/advisories/GHSA-wv8v-v4c5-v75j