{"id":"CVE-2026-98420","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: follow SMB2 session expiration semantics\n\nksmbd_session_register() destroys valid sessions after ten seconds of\ninactivity whenever a client starts another Sessi…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: follow SMB2 session expiration semantics\n\nksmbd_session_register() destroys valid sessions after ten seconds of\ninactivity whenever a client starts another Sessi…","severity":"none","published":"2026-10-14","updated":"2026-10-14","sourceUpdated":"2026-10-14T14:17:53.427","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98420","references":[{"url":"https://git.kernel.org/stable/c/c99ea7855124ca1428a1e59c2b4590aaef34eacf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d7fd1f98607f2cd358e583f9548bdf0173090a86","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-10-14T15:36:13.988Z","vendor":"Linux","product":"Linux","affected":["Linux >= ea174a91893956450510945a0c5d1a10b5323656 < c99ea7855124ca1428a1e59c2b4590aaef34eacf","Linux >= ea174a91893956450510945a0c5d1a10b5323656 < d7fd1f98607f2cd358e583f9548bdf0173090a86","Linux a6a9601ba995d0fec635324cb9fd8d14f9bea14e","Linux 1fc8a2b14ef5223f8e0b95faba2ee0a6e4d0f99d","Linux 750a2d772e9d9ff377fd32e3b6797bf2cd847a7a","Linux 6775ee7ef4b37c521aa4cf3730f54554c4875542","Linux >= 5.15.145 < 5.16","Linux >= 6.1.29 < 6.2","Linux >= 6.2.16 < 6.3","Linux >= 6.3.2 < 6.4","Linux 6.4"],"epss":0.00237,"epssPercentile":0.14688,"slug":"CVE-2026-98420","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: follow SMB2 session expiration semantics\n\nksmbd_session_register() destroys valid sessions after ten seconds of\ninactivity whenever a client starts another SessionSetup exchange. This\nconfuses Session.IdleTime with Session.ExpirationTime. Windows can create\nadditional authenticated sessions on an existing connection, so deleting\nthe older session invalidates its tree connects and makes mapped drives\nfail with STATUS_NETWORK_NAME_DELETED.\n\nThe session expiration rules require the server to change a valid session\nto expired only after its credential expiration time passes. A valid or\nexpired session otherwise keeps its connection from being scavenged.\nConnections that have not negotiated a dialect, have no sessions, or have\nonly InProgress sessions are disconnected after an implementation-specific\ntimeout. Use the Windows-compatible 45 second value and run the expiration\ncheck periodically for both TCP and SMB Direct.\n\nKeep zero as an infinite credential expiration time, and count each\nValid-to-Expired transition. Set expired sessions to InProgress when they\nreauthenticate. If authentication fails, remove the session from the\nglobal and per-connection tables immediately, including SMB3 multichannel\nconnections.\n\nRetain protection against abandoned SessionId-zero exchanges by allowing\nonly one InProgress authentication per connection. Additional exchanges\nfail with STATUS_INSUFFICIENT_RESOURCES, and stale InProgress sessions are\nreaped after the same 45 second setup timeout. This bounds the original\nunauthenticated memory-exhaustion path without evicting established\nsessions.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}