CVE-2026-77265Medium· 5.9▾ TwilightPoC availableMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, header-supplied Jira or Confluence URLs are resolved and validated before the HTTP client resolves the hostname again f…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 32.5 · likelihood 0.1 · 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.
Exploit-prediction probability, daily snapshots since Sep 23.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.4%
Exploit / PoC code exists
Last analysed / modified upstream
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, header-supplied Jira or Confluence URLs are resolved and validated before the HTTP client resolves the hostname again for the connection. An unauthenticated caller can use a DNS-rebinding hostname that returns a public address during validation and an internal address during connection, causing requests to internal or metadata services. The advisory traces the vulnerable input and processing flow through X-Atlassian-Jira-Url, X-Atlassian-Confluence-Url, validate_url_for_ssrf, and DNS rebinding, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
mcp_atlassian < 0.22.0Upgrade past the affected range:
mcp_atlassian 0.22.0Affected packages:
mcp-atlassian < 0.22.0Patched in:
mcp-atlassian 0.22.0Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-77274High· 8.2MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77267Medium· 6.5MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77249Medium· 5.3MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77261High· 7.1MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77262High· 8.6MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77266Medium· 6.5MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)