{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-81098", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-08-26T16:00:33.062Z", "datePublished": "2026-08-27T14:50:38.327Z", "dateUpdated": "2026-08-27T14:50:38.327Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-08-27T14:50:38.327Z"}, "datePublic": "2026-08-26T00:00:00.000Z", "title": "Telnyx MCP Server through 6.83.0 Missing Authentication on Streamable HTTP Transport", "descriptions": [{"lang": "en", "value": "The Telnyx MCP server exposed its HTTP transport on every interface and did not require a caller credential. packages/mcp-server/src/http.ts served MCP on the root path with a listener bound to all interfaces and parsed the caller's authentication headers in a mode that did not fail when they were absent, so a request without any credential completed initialisation and dispatched tools. Dispatch forwarded the server's own stored credentials, the Telnyx API key and client secret together with the code-execution key, to the upstream endpoint, so an unauthenticated caller able to reach the port acted with them. The current code defaults the host to loopback, requires a server API key, and enforces it in middleware."}], "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-306", "description": "Missing Authentication for Critical Function", "type": "CWE"}]}], "affected": [{"vendor": "team-telnyx", "product": "telnyx-mcp", "collectionURL": "https://github.com/team-telnyx/telnyx-node", "repo": "https://github.com/team-telnyx/telnyx-node", "defaultStatus": "unaffected", "versions": [{"version": "0", "lessThanOrEqual": "6.83.0", "status": "affected", "versionType": "semver"}], "packageURL": "pkg:npm/telnyx-mcp"}], "cpeApplicability": [], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "CRITICAL", "baseScore": 9.3, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"}}, {"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE", "version": "3.1", "baseSeverity": "CRITICAL", "baseScore": 9.1, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"}}], "references": [{"url": "https://github.com/team-telnyx/telnyx-node", "tags": ["product"]}, {"url": "https://github.com/team-telnyx/telnyx-node/pull/450", "tags": ["issue-tracking"]}, {"url": "https://github.com/team-telnyx/telnyx-node/security/advisories/GHSA-46jp-xr2h-fw7h", "tags": ["vendor-advisory"], "name": "Vendor Advisory"}, {"name": "VulnCheck Advisory: Telnyx MCP Server through 6.83.0 Missing Authentication on Streamable HTTP Transport", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/telnyx-mcp-server-through-6.83.0-missing-authentication-on-streamable-http-transport"}], "credits": [{"lang": "en", "value": "Avishai Gonen (Pluto Security)", "type": "finder"}], "x_generator": {"engine": "vulncheck-endgame"}, "source": {"discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"collectionURL": "https://github.com/team-telnyx/telnyx-node", "defaultStatus": "unaffected", "packageURL": "pkg:npm/telnyx-mcp", "product": "telnyx-mcp", "repo": "https://github.com/team-telnyx/telnyx-node", "vendor": "team-telnyx", "versions": [{"lessThanOrEqual": "6.83.0", "status": "affected", "version": "0", "versionType": "semver"}]}], "source": "disclosure@vulncheck.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "The Telnyx MCP server exposed its HTTP transport on every interface and did not require a caller credential. packages/mcp-server/src/http.ts served MCP on the root path with a listener bound to all interfaces and parsed the caller's authentication headers in a mode that did not fail when they were absent, so a request without any credential completed initialisation and dispatched tools. Dispatch forwarded the server's own stored credentials, the Telnyx API key and client secret together with the code-execution key, to the upstream endpoint, so an unauthenticated caller able to reach the port acted with them. The current code defaults the host to loopback, requires a server API key, and enforces it in middleware."}], "id": "CVE-2026-81098", "lastModified": "2026-08-27T17:20:52.297", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 9.1, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.2, "source": "disclosure@vulncheck.com", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.3, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}]}, "published": "2026-08-27T17:20:52.297", "references": [{"source": "disclosure@vulncheck.com", "url": "https://github.com/team-telnyx/telnyx-node"}, {"source": "disclosure@vulncheck.com", "url": "https://github.com/team-telnyx/telnyx-node/pull/450"}, {"source": "disclosure@vulncheck.com", "url": "https://github.com/team-telnyx/telnyx-node/security/advisories/GHSA-46jp-xr2h-fw7h"}, {"source": "disclosure@vulncheck.com", "url": "https://www.vulncheck.com/advisories/telnyx-mcp-server-through-6.83.0-missing-authentication-on-streamable-http-transport"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-306"}], "source": "disclosure@vulncheck.com", "type": "Primary"}]}

{}

{}