mcp-atlassian · FastMCP: Post-transform component authorization is skipped on direct calls
Affects mcp-atlassianSource GCVE Database
CVSS 6.8 Medium : upgrade to 0.23.1_2 when convenient.
Data as of 30 Oct 2026, 08:31 UTC
- Patch
- Available – fixed in 0.23.1_2
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:NWhat to do
Upgrade mcp-atlassian to 0.23.1_2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewmcp-atlassianpkg:brew/mcp-atlassianOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in FastMCP versions 3.4.10 and 4.1.2 that ensures authorization is applied to the final transformed component in all direct resolution and execution paths. Until upgrading, users should avoid overlapping proxy templates for protected resources and enforce authorization at the handler or server boundary rather than relying solely on component policies affected by transforms.
Description
FastMCP versions 3.0.0 through 3.4.9 and 4.0.0 through 4.1.1 contain an authorization vulnerability where direct calls to transformed components skip the final authorization check. This allows low-privilege users to invoke protected tools, resources, templates, or prompts that should be denied by policy. The issue arises because transforms modify component metadata but the authorization check is performed on the original component, not the transformed one. Fixes are available in FastMCP versions 3.4.10 and 4.1.2. Until patched, users should avoid overlapping proxy templates for protected resources and enforce authorization at the handler or server boundary.
References
- github.com/PrefectHQ/fastmcp/security/advisories/GHSA-7xgj-8392-5q4r (opens in a new tab)
- github.com/PrefectHQ/fastmcp/pull/5933 (opens in a new tab)
- github.com/PrefectHQ/fastmcp/pull/5934 (opens in a new tab)
- github.com/PrefectHQ/fastmcp/commit/85df42fbf2aa631cc81e0f986718b314128e91df (opens in a new tab)
- github.com/PrefectHQ/fastmcp/commit/8649ba5fc91a68568a69729497edeb804a064332 (opens in a new tab)
- github.com/PrefectHQ/fastmcp (opens in a new tab)
- github.com/PrefectHQ/fastmcp/releases/tag/v3.4.10 (opens in a new tab)
- github.com/PrefectHQ/fastmcp/releases/tag/v4.1.2 (opens in a new tab)