{"id":"CVE-2026-102339","title":"Telepresence: Tunnel endpoint accepts caller-supplied session ID with no ownership proof — active client sessions hijackable","summary":"Telepresence enables local development against a remote Kubernetes or OpenShift cluster. Prior to 2.31.0, the Traffic Manager Tunnel gRPC streaming endpoint parses a session ID from the first bytes of a caller-controlled message in pkg/t…","severity":"high","cvss":8.2,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N","cvssSource":"cna","cwe":["CWE-639"],"vendor":"telepresenceio","product":"telepresence","affected":["telepresence < 2.31.0"],"published":"2026-11-04","updated":"2026-11-04","sourceUpdated":"2026-11-04T20:35:34.030Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-102339","references":[{"url":"https://github.com/telepresenceio/telepresence/security/advisories/GHSA-6j3h-rp73-6rvf","label":"https://github.com/telepresenceio/telepresence/security/advisories/GHSA-6j3h-rp73-6rvf"},{"url":"https://github.com/telepresenceio/telepresence/pull/4217","label":"https://github.com/telepresenceio/telepresence/pull/4217"},{"url":"https://github.com/telepresenceio/telepresence/commit/1312482488b771742dbedd3015f9a81a27532de6","label":"https://github.com/telepresenceio/telepresence/commit/1312482488b771742dbedd3015f9a81a27532de6"},{"url":"https://github.com/telepresenceio/telepresence/commit/36458b65a010d2b316af48cd90e193ba190785d9","label":"https://github.com/telepresenceio/telepresence/commit/36458b65a010d2b316af48cd90e193ba190785d9"},{"url":"https://github.com/telepresenceio/telepresence/releases/tag/v2.31.0","label":"https://github.com/telepresenceio/telepresence/releases/tag/v2.31.0"}],"tags":["cve.org"],"ingestedAt":"2026-11-05T21:36:00.563Z","epss":0.00287,"epssPercentile":0.21329,"slug":"CVE-2026-102339","body":"## Overview\n\nTelepresence enables local development against a remote Kubernetes or OpenShift cluster. Prior to 2.31.0, the Traffic Manager Tunnel gRPC streaming endpoint parses a session ID from the first bytes of a caller-controlled message in pkg/tunnel/message.go and passes it to state.Tunnel without verifying that the caller owns the active session. An attacker who obtains a valid active session ID through log leakage, cluster-internal channels, or the unauthenticated ArriveAsClient endpoint can attach a routed tunnel to that session and gain its network routing capabilities. UUID4 session IDs make cold brute force impractical. This vulnerability is fixed in 2.31.0.\n\n## Affected\n\n- `telepresence < 2.31.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":45.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}