CVSS 4.0
8.8 highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:NCVE-2026-77274
High (8.8) in mcp-atlassian mcp atlassian. EPSS 0.3% chance of exploitation in the next 30 days. Fixed in mcp-atlassian 0.22.0.
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_url_for_ssrf has a backslash authority confusion because it interprets the authority differently from the Requests connection layer in the header-based Jira and Confluence URL authentication flow. A crafted URL can validate as an external hostname while the HTTP client connects to an internal host, permitting server-side requests to protected network resources. This issue is fixed in version 0.22.0.
Severity
CVSS 3.1
8.2 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N- EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 26% of CVEs (scores of 2026-10-31)
- CWE
- CWE-918
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mcp-atlassian:mcp_atlassian
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-hgcf-4mq8-5266 | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |
| PYSEC-2026-4096 | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |
References
- https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460
- https://github.com/sooperset/mcp-atlassian/pull/1448
- https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-hgcf-4mq8-5266
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-hgcf-4mq8-5266