CVE-2026-255367.1HighCWE-362

CVE-2026-25536: @modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuse

modelcontextprotocol · typescript-sdk

Vendor fix available · Affected: modelcontextprotocol typescript-sdk · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.3%probability of exploitation in the next 30 days

22nd percentile

050100

Higher than 22% of scored CVEs

7.1HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

modelcontextprotocol · typescript-sdk>= 1.10.0, < 1.26.0

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Race Condition · Race Conditions
Vendor: modelcontextprotocol
Published: February 2026
Band: Unlikely (under 1%), February 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-25536 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.