GHSA-8ffx-6c2g-75cc: 
Python Analyse et atténuation de la vulnérabilité

Summary

An unrestricted link_id lets a caller transform the link-removal DELETE request into an issue-deletion request when the Jira credential has permission to delete the target issue.

Details

jira_remove_issue_link treated the caller-controlled link_id as a URL path component without validating that it was an atomic numeric identifier. A value such as ../issue/PROJ-1 caused the client to construct /rest/api/2/issueLink/../issue/PROJ-1, which Requests normalized to /rest/api/2/issue/PROJ-1 while preserving the DELETE method. Consequently, a caller permitted to use the link-removal tool could invoke issue deletion without access to the dedicated issue-deletion MCP tool. Exploitation requires write mode and a backing Jira credential authorized to delete the target issue.

PoC

mixin.remove_issue_link(link_id) with link_id like "../issue/PROJ-1".

Impact

Theoretical scenario where issue comment tools are allowed but issue delete is not. General improvement to link_id handling. Exploitation requires write mode and a backing Jira credential authorized to delete the target issue. Patch for links.py (also available along w/ tests via https://github.com/cblacknygc/mcp-atlassian/tree/security/jira-link-remove-delete-issue branch): if not link_id: raise ValueError("Link ID is required") +if not link_id.isascii() or not link_id.isdecimal():

• raise ValueError("Link ID must contain only ASCII digits") try: self.jira.remove_issue_link(link_id)

Fix

Fixed in mcp-atlassian 0.24.1.