CVE-2026-77243: MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)
CVE-2026-77243 is a high-severity flaw (CVSS 8.8) affecting mcp atlassian. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, ENABLED_TOOLS and TOOLSETS are applied when tools are listed but are not rechecked when a tools/call request is dispatched. A client that knows a hidden tool name can directly invoke excluded read, write, or delete tools despite the operator's configured least-privilege restrictions. The advisory traces the vulnerable input and pr
Why this priority
- High severity
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 8.8 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 55%) |
| CISA exploited list | No |
| Weakness | CWE-862 |
| Published | 2026-09-22 |
| Last modified | 2026-09-29 |
Last updated 2026-09-29 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-77243?
mcp atlassian: upgrade to 0.22.0. Exact commands for each OS are on this page.
Is CVE-2026-77243 being exploited?
CVE-2026-77243 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-77243 affect?
CVE-2026-77243 affects mcp atlassian. Severity is high (CVSS 8.8). MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, ENABLED_TOOLS and TOOLSETS are applied when tools are listed but are not rechecked when a tools/call request is dispatched
How urgent is CVE-2026-77243?
Priority 47/100. High severity; Public exploit reference
Software pages
Atlassian Confluence vulnerabilities · Atlassian Jira vulnerabilities
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