CVE-2026-77244
10.0
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
Exploitability: 3.9 / Impact: 5.8
Source: security-advisories@github.com (Secondary)
Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the HTTP transport accepts requests without a verified user identity and downstream fetcher construction falls back to the operator's globally configured Jira or Confluence credentials. A network client that can reach the MCP endpoint can invoke Atlassian tools as the operator, including read and write operations available to that account. The advisory traces the vulnerable input and processing flow through UserTokenMiddleware, AtlassianOpaqueTokenVerifier, _get_fetcher, and streamable-http, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
Affected (1)
Products: Mcp Atlassian: Mcp Atlassian
Configuration A
| Vulnerable Software | Affected Versions |
|---|---|
| version < 0.22.0 |
Related CWEs
CWE-287
Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
CWE-303
Incorrect Implementation of Authentication Algorithm
The requirements for the product dictate the use of an established authentication algorithm, but the implementation of the algorithm is incorrect.
CWE-862
Missing Authorization
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
References (4)
Source: security-advisories@github.com
Patch
Source: security-advisories@github.com
Release Notes
Source: security-advisories@github.com
ExploitVendor Advisory
Timeline
No history available yet.