CVE-2026-27826
8.2 · HIGHOverview
CVE-2026-27826 is a high-severity vulnerability affecting sooperset mcp_atlassian. It was published on March 10, 2026 and has a CVSS 3.1 base score of 8.2 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.2, rated HIGH. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical Description
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 `Authorization` header. 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.
Remediation
Check the references section for vendor advisories and patches from sooperset. Update mcp_atlassian to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| sooperset | mcp_atlassian | >= 0, < 0.17.0 | Affected |
Frequently Asked Questions
What is CVE-2026-27826?
CVE-2026-27826 is a high-severity vulnerability affecting sooperset mcp_atlassian. It was published on March 10, 2026 and has a CVSS 3.1 base score of 8.2 (HIGH).
How severe is CVE-2026-27826?
This vulnerability has a CVSS 3.1 base score of 8.2, rated HIGH. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-27826?
Check the references section for vendor advisories and patches from sooperset. Update mcp_atlassian to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-27826?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-27826 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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