MCP Atlassian: SSRF Protection Bypass

Environment- Project: sooperset/mcp-atlassian- Affected function: validateurlforssrf- Affected path: header-based Jira/Confluence URL authentication flow- Tested endpoint: POST /mcp- Tested version: 2.14.5 DescriptionThe SSRF protection in validateurlforssrf can be bypassed with a URL containing ...

PYSEC-2026-4087 MCP Atlassian: Incomplete path traversal fix allows intra-CWD module overwrite and RCE (bypass of GHSA-xjgw-4wvw-rgm4)

Summary The path traversal fix introduced in v0.17.0 GHSA-xjgw-4wvw-rgm4 is incomplete. validatesafepath is called without an explicit basedir, defaulting to os.getcwd. In standard container deployments the process CWD is the application directory e.g. /app, so paths within that directory,...

[mcp-atlassian] Authentication bypass in HTTP transport: AtlassianOpaqueTokenVerifier accepts any non-empty token

Descriptionmcp-atlassian deploys in two common patterns: Pattern A single-user, server-side credentials: operator sets JIRAUSERNAME + JIRAAPITOKEN or CONFLUENCEUSERNAME + CONFLUENCEAPITOKEN in environment variables. Server uses these to call Jira/Confluence. This is the documented quickstart...

PYSEC-2026-4088 MCP Atlassian: Arbitrary file read/exfiltration via upload_attachment missing validate_safe_path()

Summary The uploadattachment method in confluence/attachments.py reads and uploads arbitrary local files to Confluence without calling validatesafepath. Both download methods downloadattachment at line 223, downloadcontentattachments at line 272 correctly call validatesafepath before writing file...

MCP Atlassian: OAuth fallback token storage writes plaintext access and refresh tokens with group-readable permissions

SummaryWhen OAuth tokens are saved, MCP Atlassian always writes a plaintext fallback copy under /.mcp-atlassian/oauth-.json. The fallback file is created with the process default umask rather than restrictive permissions. In this environment the file was created as mode 0664, exposing access and...

PYSEC-2026-4084 mcp-atlassian has an incomplete SSRF remediation

Summary The UserTokenMiddleware extracts URLs from X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url HTTP headers and passes them directly to API client constructors without any SSRF validation. Affected Package - Ecosystem: PyPI - Package: mcp-atlassian - Affected versions: all versions before...

PYSEC-2026-4103 [mcp-atlassian] Authentication bypass in HTTP transport: AtlassianOpaqueTokenVerifier accepts any non-empty token

Description mcp-atlassian deploys in two common patterns: Pattern A single-user, server-side credentials: operator sets JIRAUSERNAME + JIRAAPITOKEN or CONFLUENCEUSERNAME + CONFLUENCEAPITOKEN in environment variables. Server uses these to call Jira/Confluence. This is the documented quickstart...

PYSEC-2026-4092 MCP Atlassian: Arbitrary server-local file upload to Jira/Confluence attachments via unrestricted file_path parameters

Summary The Jira and Confluence attachment upload tools accept caller-controlled file path parameters and read those paths from the MCP server's local filesystem before uploading the file as an Atlassian attachment. In local stdio deployments, this can expose files readable by the user's MCP...

MCP Atlassian: Arbitrary server-local file upload to Jira/Confluence attachments via unrestricted file_path parameters

SummaryThe Jira and Confluence attachment upload tools accept caller-controlled file path parameters and read those paths from the MCP server's local filesystem before uploading the file as an Atlassian attachment.In local stdio deployments, this can expose files readable by the user's MCP proces...

MCP Atlassian: Arbitrary File Read via Upload Attachment Tools

SummaryThe upload attachment tools in both Confluence and Jira accept arbitrary file paths without path traversal validation. The uploadattachment methods read any file accessible to the server process and upload it to a Confluence page or Jira issue. Despite the existence of a validatesafepath...

MCP Atlassian: ENABLED_TOOLS / Toolset authorization bypass

SummaryENABLEDTOOLS and TOOLSETS filters are enforced at tools/list time only. tools/call dispatches from the full unfiltered tool registry 73 tools. Any user with access to the server endpoint that knows a tool name can invoke it directly. Tool names are not secret since mcp-atlassian is open...

MCP Atlassian: Arbitrary File Read & Exfiltration (Confused Deputy) in JIRA update_issue

SummaryA critical Confused Deputy Arbitrary File Read & Exfiltration vulnerability in the Atlassian MCP server Python allows an AI agent to exfiltrate sensitive host files and environment secrets. By providing absolute system paths to the attachments parameter of the updateissue tool, an agent ca...

PYSEC-2026-4093 MCP Atlassian: Reflected XSS in OAuth Setup Callback Handler

Summary The OAuth 2.0 setup wizard's local callback HTTP server reflects the error query parameter directly into an HTML response without any sanitization or encoding. An attacker can craft a malicious callback URL containing JavaScript in the error parameter that executes in the victim's browser...

MCP Atlassian: Arbitrary file read via confluence_upload_attachment allows exfiltration of server credentials

SummaryMissing path validation in confluenceuploadattachment allows any authenticated MCP client to read arbitrary files from the server filesystem and exfiltrate their contents to Confluence. On Linux deployments, /proc/self/environ yields all runtime secrets in a single call.---...

MCP Atlassian: Path traversal in upload_attachment allows arbitrary file read and exfiltration via MCP tool call

SummaryThe uploadattachment functions in both the Jira and Confluence modules accept a user-controlled filepath parameter and open the specified file for reading without calling validatesafepath. An authenticated MCP client can supply an arbitrary path such as /etc/passwd or /proc/self/environ,...

MCP Atlassian: Jira and Confluence attachment upload tools can read arbitrary server-local files

SummaryMCP Atlassian exposes Jira and Confluence attachment upload tools that accept arbitrary local filesystem paths and upload those file contents to Atlassian. In HTTP or multi-user deployments, an MCP caller who can invoke write tools can cause the server to read any file accessible to the MC...

MCP Atlassian: Arbitrary local file READ via unconstrained file_path in upload_attachment (Confluence + Jira)

SummaryThis is an arbitrary local file READ vulnerability on the Confluence and Jira uploadattachment tool paths. It's the symmetric counterpart of the file-write vulnerability you patched as CVE-2026-27825. The write direction was fixed; the read direction was left open.Reporter: Sean...

MCP Atlassian: SSRF redirect protection missing for basic-auth and OAuth authentication branches

Summarymakessrfsafehook blocks HTTP redirects to private/internal IPs by validating the Location header before the client follows a 3xx response. The problem is that this hook is only attached in one of three authentication branches — the header-PAT path. Basic auth and OAuth branches skip it...

MCP Atlassian: HTTP upload tools accept arbitrary server-local file paths

sooperset/mcp-atlassian: HTTP upload tools can attach arbitrary server-local filesDate: 2026-05-05Target: sooperset/mcp-atlassianCommit: d8bc78698a63cb6b321c7ca796d6329d448f7f6d Summarymcp-atlassian supports HTTP/SSE deployment for persistent, remote, and multi-user use. In that mode, write-capab...

MCP Atlassian: Insecure File Permissions on OAuth Token Storage

SummaryThe OAuth token fallback file storage in OAuthConfig.savetokenstofile creates token files containing access tokens, refresh tokens, and cloud IDs with default filesystem permissions typically 0644 on Linux, world-readable. Any local user on a shared system can read these files to obtain fu...