CVE-2026-77267: sooperset mcp-atlassian · Server-Side Request Forgery (SSRF)
Affects sooperset mcp-atlassianSource CVE Database V5
Mentioned vulnerabilities
Not known to be exploited · CVSS 8.3 High : upgrade to 0.22.0 soon.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.22.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 22 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade mcp-atlassian and sooperset/mcp-atlassian to 0.22.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| soopersetmcp-atlassian | Affected
| Fixed in
|
GitHubsooperset/mcp-atlassianpkg:github/sooperset/mcp-atlassianOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade MCP Atlassian to version 0.22.0 or later, where this SSRF vulnerability is fixed. Since this is an on-premises component, users must apply the update themselves. Patch status is confirmed fixed in 0.22.0. No additional mitigations are specified.
Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url headers are processed by _process_authentication_headers and used to construct Atlassian fetchers without calling validate_url_for_ssrf. A caller who can set these headers can supply an internal or metadata-service URL and cause the server to send requests to that destination, bypassing the incomplete CVE-2026-27826 remediation. This issue is fixed in version 0.22.0.
References
- github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3 (opens in a new tab)
- github.com/sooperset/mcp-atlassian/pull/1448 (opens in a new tab)
- github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460 (opens in a new tab)
- github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0 (opens in a new tab)