CVE-2026-63127
NVD: RMCP is an official Rust SDK for the Model Context Protocol. NVD: Prior to 2.0.0, the rmcp crate's OAuth implementation in crates/rmcp/src/transport/auth.rs omits the RFC 9728 resource field from ResourceServerMetadata and allows discover_oauth_server_via_resource_metadata to use protected-resource metadata without... NVD: A malicious MCP server can publish metadata for a different legitimate MCP resource and its authorization server, causing a victim who connects and completes the authorization flow to obtain a legitimate access token that the client subsequently sends to the...
8.2 Severity
HIGH EPSS
0.0019 (10) KEV
-
Source-published summary
NVD: RMCP is an official Rust SDK for the Model Context Protocol. NVD: Prior to 2.0.0, the rmcp crate's OAuth implementation in crates/rmcp/src/transport/auth.rs omits the RFC 9728 resource field from ResourceServerMetadata and allows discover_oauth_server_via_resource_metadata to use protected-resource metadata without... NVD: A malicious MCP server can publish metadata for a different legitimate MCP resource and its authorization server, causing a victim who connects and completes the authorization flow to obtain a legitimate access token that the client subsequently sends to the...
Possible impact
This high severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for high severity review.
Affected context
Affected product or version requires source confirmation.
Remediation / advisory
Patch confirmed by source text; fixed version context: 2.0.0..
Why it matters
This high severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for high severity review.; CVSS 8.2 (HIGH); EPSS percentile 10; not listed in KEV; Patch confirmed by source text; fixed version context: 2.0.0; sources: NVD, OSV.
What to verify
Confirm affected product/version, vendor advisory, patch or mitigation, and exposure.
Exposure hint
exposure unknown
Impact tags
Urgency reasons
Source-derived note
Summary derived from NVD / OSV description; unsafe procedural detail is not shown.
Redaction metadata
- source summary used
- True
- fallback summary used
- False
- unsafe procedural detail present
- false
- raw source displayed
- false
- public summary redacted
- true
Remediation handoff
Public-safe static handoff for human/Codex remediation planning. Scan, patch, external execution, and auto remediation are disabled.
Safety note
This radar shows source-published defensive context only. Exploit procedures, exploit strings, scanner commands, and auto-remediation are not provided.