SSRF in Mcp-Atlassian Mcp Atlassian
CVE-2026-77261
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, _make_ssrf_safe_hook is omitted from JiraFetcher and ConfluenceFetcher sessions created through the basic-auth and oauth_pat branches. If an attacker-controlled or compromised configured Atlassian instance returns a redirect to an internal address, those sessions can follow the redirect without revalidating its destination. This issue is fixed in version 0.22.0.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (31.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
- Mcp-Atlassian Mcp Atlassian
- Sooperset Mcp-Atlassian — versions < 0.22.0
Weakness classification (CWE)
References
- github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e… (Patch)
- github.com/sooperset/mcp-atlassian/pull/1448 (Patch)
- github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0 (Release Notes)
- github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6529-c226-h328 (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-77261?
- CVE-2026-77261 is a high-severity vulnerability in Mcp-Atlassian Mcp Atlassian, classified under Server-Side Request Forgery (SSRF). CVSS score: 7.1/10. Published 2026-09-22.
- How severe is CVE-2026-77261?
- High severity. CVSS v3 base score is 7.1 out of 10.