CVE-2026-77259 (GCVE-0-2026-77259)
Vulnerability from cvelistv5 – Published: 2026-09-22 18:45 – Updated: 2026-09-26 00:04
VLAI
EPSS
VEX
Title
MCP Atlassian: Arbitrary file read via confluence_upload_attachment allows exfiltration of server credentials
Summary
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, confluence_upload_attachment opens a caller-selected server-local file without checking that the resolved path remains in the workspace. A caller can upload environment files, credentials, or other readable host data to a Confluence page and retrieve it through Atlassian. The advisory traces the vulnerable input and processing flow through confluence_upload_attachment, file_path, and open(file_path, "rb"), which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
Severity
7.7 (High)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-26 00:03 UTC
CWE
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/sooperset/mcp-atlassian/securi… | x_refsource_CONFIRM |
| https://github.com/sooperset/mcp-atlassian/pull/1448 | x_refsource_MISC |
| https://github.com/sooperset/mcp-atlassian/commit… | x_refsource_MISC |
| https://github.com/sooperset/mcp-atlassian/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| sooperset | mcp-atlassian |
Affected:
< 0.22.0
|
guessed |
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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