CVE-2026-27826
- Source
- https://cve.org/CVERecord?id=CVE-2026-27826
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27826.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-27826
- Aliases
- Published
- 2026-03-10T18:46:12.069Z
- Modified
- 2026-07-15T01:48:51.504774856Z
- Severity
-
- 8.2 (High) CVSS_V3 - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N CVSS Calculator
- Summary
- MCP Atlassian has SSRF via unvalidated X-Atlassian-Jira-Url / X-Atlassian-Confluence-Url headers
- Details
-
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to version 0.17.0, an unauthenticated attacker who can reach the mcp-atlassian HTTP endpoint can force the server process to make outbound HTTP requests to an arbitrary attacker-controlled URL by supplying two custom HTTP headers without an
Authorizationheader. No authentication is required. The vulnerability exists in the HTTP middleware and dependency injection layer — not in any MCP tool handler - making it invisible to tool-level code analysis. In cloud deployments, this could enable theft of IAM role credentials via the instance metadata endpoint (169[.]254[.]169[.]254). In any HTTP deployment it enables internal network reconnaissance and injection of attacker-controlled content into LLM tool results. Version 0.17.0 fixes the issue. - Database specific
{ "cwe_ids": [ "CWE-918" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27826.json", "cna_assigner": "GitHub_M" }- References
-
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27826.json
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-7r34-79r5-rcc9
- https://nvd.nist.gov/vuln/detail/CVE-2026-27826
- https://github.com/sooperset/mcp-atlassian/commit/5cd697dfce9116ef330b8dc7a91291640e0528d9
Affected packages
Git / github.com/sooperset/mcp-atlassian
Affected ranges
- Type
- GIT
- Repo
- https://github.com/sooperset/mcp-atlassian
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedFixedFixed
- Database specific
{ "cpe": "cpe:2.3:a:sooperset:mcp_atlassian:*:*:*:*:*:*:*:*", "extracted_events": [ { "introduced": "0" }, { "fixed": "0.17.0" } ], "source": [ "CPE_RANGE", "REFERENCES" ] }