CVEvulnerability

CVE-2026-77250

6.1 MEDIUM Published 2026-09-22 Modified 2026-09-29 Official page ↗
Status
Analyzed
Published
2026-09-22
Last modified
2026-09-29
Assigner
[email protected]
CVSS 3.1 ([email protected])
6.1 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Weaknesses
CWE-312

Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, OAuthConfig writes a plaintext fallback file containing access and refresh tokens under the user's .mcp-atlassian directory using process-default permissions. On systems with a permissive umask, same-group or other local users and processes can read the persisted tokens and reuse the associated Atlassian access. The advisory traces the vulnerable input and processing flow through OAuthConfig._save_tokens, ~/.mcp-atlassian/oauth-<client_id>.json, access_token, and refresh_token, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

Affected configurations

• mcp-atlassian mcp atlassian (< 0.22.0)

Related

Weakness · CWE (1)

  • CWE-312 Cleartext Storage of Sensitive Information weakness

References