CVE-2026-98420

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98420", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.348Z", "datePublished": "2026-10-14T13:27:49.599Z", "dateUpdated": "2026-10-19T09:19:13.954Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:19:13.954Z"}, "descriptions": [{"lang": "en", "value": "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 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."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/connection.c", "fs/smb/server/connection.h", "fs/smb/server/mgmt/user_session.c", "fs/smb/server/mgmt/user_session.h", "fs/smb/server/proc.c", "fs/smb/server/server.c", "fs/smb/server/smb2pdu.c", "fs/smb/server/smb2pdu.h", "fs/smb/server/stats.h"], "versions": [{"version": "ea174a91893956450510945a0c5d1a10b5323656", "lessThan": "c99ea7855124ca1428a1e59c2b4590aaef34eacf", "status": "affected", "versionType": "git"}, {"version": "ea174a91893956450510945a0c5d1a10b5323656", "lessThan": "d7fd1f98607f2cd358e583f9548bdf0173090a86", "status": "affected", "versionType": "git"}, {"version": "a6a9601ba995d0fec635324cb9fd8d14f9bea14e", "status": "affected", "versionType": "git"}, {"version": "1fc8a2b14ef5223f8e0b95faba2ee0a6e4d0f99d", "status": "affected", "versionType": "git"}, {"version": "750a2d772e9d9ff377fd32e3b6797bf2cd847a7a", "status": "affected", "versionType": "git"}, {"version": "6775ee7ef4b37c521aa4cf3730f54554c4875542", "status": "affected", "versionType": "git"}, {"version": "5.15.145", "lessThan": "5.16", "status": "affected", "versionType": "semver"}, {"version": "6.1.29", "lessThan": "6.2", "status": "affected", "versionType": "semver"}, {"version": "6.2.16", "lessThan": "6.3", "status": "affected", "versionType": "semver"}, {"version": "6.3.2", "lessThan": "6.4", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/connection.c", "fs/smb/server/connection.h", "fs/smb/server/mgmt/user_session.c", "fs/smb/server/mgmt/user_session.h", "fs/smb/server/proc.c", "fs/smb/server/server.c", "fs/smb/server/smb2pdu.c", "fs/smb/server/smb2pdu.h", "fs/smb/server/stats.h"], "versions": [{"version": "6.4", "status": "affected"}, {"version": "0", "lessThan": "6.4", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.8", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "7.2.8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "7.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.145"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.29"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2.16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.3.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/c99ea7855124ca1428a1e59c2b4590aaef34eacf"}, {"url": "https://git.kernel.org/stable/c/d7fd1f98607f2cd358e583f9548bdf0173090a86"}], "title": "ksmbd: follow SMB2 session expiration semantics", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/server/connection.c", "fs/smb/server/connection.h", "fs/smb/server/mgmt/user_session.c", "fs/smb/server/mgmt/user_session.h", "fs/smb/server/proc.c", "fs/smb/server/server.c", "fs/smb/server/smb2pdu.c", "fs/smb/server/smb2pdu.h", "fs/smb/server/stats.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "c99ea7855124ca1428a1e59c2b4590aaef34eacf", "status": "affected", "version": "ea174a91893956450510945a0c5d1a10b5323656", "versionType": "git"}, {"lessThan": "d7fd1f98607f2cd358e583f9548bdf0173090a86", "status": "affected", "version": "ea174a91893956450510945a0c5d1a10b5323656", "versionType": "git"}, {"status": "affected", "version": "a6a9601ba995d0fec635324cb9fd8d14f9bea14e", "versionType": "git"}, {"status": "affected", "version": "1fc8a2b14ef5223f8e0b95faba2ee0a6e4d0f99d", "versionType": "git"}, {"status": "affected", "version": "750a2d772e9d9ff377fd32e3b6797bf2cd847a7a", "versionType": "git"}, {"status": "affected", "version": "6775ee7ef4b37c521aa4cf3730f54554c4875542", "versionType": "git"}, {"lessThan": "5.16", "status": "affected", "version": "5.15.145", "versionType": "semver"}, {"lessThan": "6.2", "status": "affected", "version": "6.1.29", "versionType": "semver"}, {"lessThan": "6.3", "status": "affected", "version": "6.2.16", "versionType": "semver"}, {"lessThan": "6.4", "status": "affected", "version": "6.3.2", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/smb/server/connection.c", "fs/smb/server/connection.h", "fs/smb/server/mgmt/user_session.c", "fs/smb/server/mgmt/user_session.h", "fs/smb/server/proc.c", "fs/smb/server/server.c", "fs/smb/server/smb2pdu.c", "fs/smb/server/smb2pdu.h", "fs/smb/server/stats.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.4"}, {"lessThan": "6.4", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.8", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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 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."}], "id": "CVE-2026-98420", "lastModified": "2026-10-19T10:18:47.533", "metrics": {}, "published": "2026-10-14T14:17:53.427", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c99ea7855124ca1428a1e59c2b4590aaef34eacf"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d7fd1f98607f2cd358e583f9548bdf0173090a86"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: ksmbd: follow SMB2 session expiration semantics", "id": "2552201", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2552201"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-826", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nksmbd: follow SMB2 session expiration semantics\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.\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.\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.\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.", "A flaw was found in the Linux kernel's ksmbd module. A remote client can cause a Denial of Service (DoS) by initiating a new session setup exchange on an existing Server Message Block (SMB) connection. Due to an error where session idle time is confused with credential expiration time, the server prematurely terminates valid sessions after a brief period of inactivity. This leads to the invalidation of active connections and causes mapped network drives to disconnect unexpectedly."], "name": "CVE-2026-98420", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-14T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98420\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98420\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98420.mbox"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ea174a91893956450510945a0c5d1a10b5323656,c99ea7855124ca1428a1e59c2b4590aaef34eacf)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ea174a91893956450510945a0c5d1a10b5323656,d7fd1f98607f2cd358e583f9548bdf0173090a86)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "a6a9601ba995d0fec635324cb9fd8d14f9bea14e"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "1fc8a2b14ef5223f8e0b95faba2ee0a6e4d0f99d"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "750a2d772e9d9ff377fd32e3b6797bf2cd847a7a"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "6775ee7ef4b37c521aa4cf3730f54554c4875542"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[5.15.145,5.16)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.1.29,6.2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.2.16,6.3)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.3.2,6.4)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "6.4"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.4)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.8,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-15T03:30:03.250290+00:00", "updated": "2026-10-19T22:15:05.303783+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}