Baitaphish
Security intelligence
SearchLatest briefing
CVE Explorer

CVE-2026-27826

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 t
Lifecycle PUBLISHED1 preserved revisionFact urn:baitaphish:canonical-cve-fact-revision:v2:feefc99fbe34b4845c914b0a9dae710ae54c4d0a950256740532eb6df97d0420
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0

Affected products and versions

1 source assertion
{"product":"mcp-atlassian","vendor":"sooperset","versions":[{"status":"affected","version":"< 0.17.0"}]}
  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:6b2d7e90e546bd41226cd77a2d694e940da422da66b5bbf126e565213e0bd928 · sha256:d0d8474ac23aea62… · /containers/cna/affected/0

Provider-owned CVSS observations

1 source assertion
{"metric":{"attackComplexity":"LOW","attackVector":"ADJACENT_NETWORK","availabilityImpact":"NONE","baseScore":8.2,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N","version":"3.1"},"metric_type":"cvssV3_1"}
  • cve_program_cvelist_v5cvss
    urn:baitaphish:normalized-source-record:v2:6b2d7e90e546bd41226cd77a2d694e940da422da66b5bbf126e565213e0bd928 · sha256:d0d8474ac23aea62… · /containers/cna/metrics/0/cvssV3_1

CWE assertions

1 source assertion
{"cweId":"CWE-918","description":"CWE-918: Server-Side Request Forgery (SSRF)","lang":"en","type":"CWE"}
  • cve_program_cvelist_v5cwe
    urn:baitaphish:normalized-source-record:v2:6b2d7e90e546bd41226cd77a2d694e940da422da66b5bbf126e565213e0bd928 · sha256:d0d8474ac23aea62… · /containers/cna/problemTypes/0/descriptions/0

Source references

2 source assertions
{"name":"https://github.com/sooperset/mcp-atlassian/commit/5cd697dfce9116ef330b8dc7a91291640e0528d9","tags":["x_refsource_MISC"],"url":"https://github.com/sooperset/mcp-atlassian/commit/5cd697dfce9116ef330b8dc7a91291640e0528d9"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:6b2d7e90e546bd41226cd77a2d694e940da422da66b5bbf126e565213e0bd928 · sha256:d0d8474ac23aea62… · /containers/cna/references/1
{"name":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-7r34-79r5-rcc9","tags":["x_refsource_CONFIRM"],"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-7r34-79r5-rcc9"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:6b2d7e90e546bd41226cd77a2d694e940da422da66b5bbf126e565213e0bd928 · sha256:d0d8474ac23aea62… · /containers/cna/references/0

Attribution and limitations

  • CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →

Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.

← Back to CVE Explorer