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TI-2026-20645 Aliases CVE-2026-25536GHSA-345p-7cg4-v4c7

@modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuse

Priority LOW 31CWE-362Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.

Summary

MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. From version 1.10.0 to 1.25.3, cross-client response data leak when a single McpServer/Server and transport instance is reused across multiple client connections, most commonly in stateless StreamableHTTPServerTransport deployments. This issue has been patched in version 1.26.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00293 22nd percentileScored 2026-11-07
Fix Fixed typescript-sdk (modelcontextprotocol): 1.26.0@modelcontextprotocol/sdk (npm): 1.26.0Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MLflowtypescript-sdk1.10.0 to before 1.26.01.26.0Patch availableCNA
—@modelcontextprotocol/sdk (npm)1.10.0 to before 1.26.01.26.0Patch availableGHSA-345p-7cg4-v4c7
  • typescript-sdk VendorMLflow Affected 1.10.0 to before 1.26.0 Fixed in 1.26.0 Patch available CNA
  • @modelcontextprotocol/sdk (npm) Vendor— Affected 1.10.0 to before 1.26.0 Fixed in 1.26.0 Patch available GHSA-345p-7cg4-v4c7

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:lfprojects:mcp_typescript_sdk:*:*:*:*:*:*:*:*1.10.0 to before 1.26.0VulnerableMLflow
  • cpe:2.3:a:lfprojects:mcp_typescript_sdk:*:*:*:*:*:*:*:* Versions 1.10.0 to before 1.26.0 Vulnerable ·MLflow

Remediation

  • Fix · CNA typescript-sdk (modelcontextprotocol) Fixed in 1.26.0
  • Fix · GHSA-345p-7cg4-v4c7 @modelcontextprotocol/sdk (npm) Fixed in 1.26.0 Advisory →

Red Hat 1 advisory

  • RHSA-2026:3960 Released 2026-03-06 · Red Hat rating Important
    Red Hat Ansible Automation Platform 2.6 Container Release Update
    • Red Hat Ansible Automation Platform 2.6 registry.redhat.io/ansible-automation-platform-26/de-minimal-rhel9, registry.redhat.io/ansible-automation-platform-26/de-supported-rhel9, registry.redhat.io/ansible-automation-platform-26/ee-minimal-rhel9 +9

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Ansible Automation Platform 2.6Fixed RHSA-2026:3960
Not affected: 1 product
  • Red Hat Ansible Automation Platform 2.6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-25536
  2. 2026-10-03 Alias added: GHSA-345p-7cg4-v4c7

References

Advisory 4

Other 1

  • TI-2026-00421 MCP TypeScript SDK UriTemplate Exploded Array Pattern ReDoS CVSS 4.0HIGH 8.7
  • TI-2025-40850 DNS Rebinding Protection Disabled by Default in Model Context Protocol TypeScript SDK for Servers Running on Localhost CVSS 4.0HIGH 7.6

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences