CVE-2026-77266Medium· 6.5▾ TwilightPoC availableMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, upload_attachment accepts absolute paths and traversal sequences without constraining the resolved path to the server w…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 35.8 · likelihood 0 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Exploit / PoC code exists
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, upload_attachment accepts absolute paths and traversal sequences without constraining the resolved path to the server workspace. An MCP caller with attachment access can read a chosen server-local file and exfiltrate it through Jira or Confluence. The advisory traces the vulnerable input and processing flow through upload_attachment, file_path, and path traversal, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-77262High· 8.6MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77253High· 7.1MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77270Medium· 6.5MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-73496High· 7.7MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77257High· 8.3MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77255High· 8.6MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)