23 Oct 2026 15:48:27 UTC
MCP Atlassian: SSRF redirect protection missing for basic-auth and OAuth authentication branches
cve-program · CVE-2026-77261 · Published
CVE-2026-77261
MCP Atlassian: SSRF redirect protection missing for basic-auth and OAuth authentication branches
CVSS 3.1 7.1 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-77261
PublishedMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, _make_ssrf_safe_hook is omitted from JiraFetcher and ConfluenceFetcher sessions created through the basic-auth and oauth_pat branches. If an attacker-controlled or compromised configured Atlassian instance returns a redirect to an internal address, those sessions can follow the redirect without revalidating its destination. This issue is fixed in version 0.22.0.
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