Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
mcp-atlassian versions before 0.22.0 accept Jira and Confluence URLs from the X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url HTTP headers and use them for outbound requests without SSRF validation. An attacker who can send HTTP requests to the server can make it issue authenticated requests to arbitrary internal or metadata endpoints. Upgrade to version 0.22.0 or later; the source gives no workaround.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.3 | High | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0032, the 25th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:09 UTC First seen by agentprime
- 31 Oct 2026, 14:09 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-5wf4-jqxh-8gm3
- OSV: GHSA-5wf4-jqxh-8gm3
- github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3
- nvd.nist.gov/vuln/detail/CVE-2026-77267
- github.com/sooperset/mcp-atlassian/pull/1448
- github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460
- github.com/sooperset/mcp-atlassian
- github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0