{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89774", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.765Z", "datePublished": "2026-09-16T08:24:21.248Z", "dateUpdated": "2026-09-16T14:38:26.042Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-16T14:38:26.042Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: SCO: hold sk properly in sco_conn_ready\n\nsk deref in sco_conn_ready must be done either under conn->lock, or\nholding a refcount, to avoid concurrent close. conn->sk and parent sk is\ncurrently accessed without either, and without checking parent->sk_state:\n\n [Task 1] [Task 2]\n sco_sock_release\n sco_conn_ready\n sk = conn->sk\n lock_sock(sk)\n conn->sk = NULL\n lock_sock(sk)\n release_sock(sk)\n sco_sock_kill(sk)\n UAF on sk deref\n\nand similarly for access to sco_get_sock_listen() return value.\n\nFix possible UAF by holding sk refcount in sco_conn_ready() and making\nsco_get_sock_listen() increase refcount. Also recheck after lock_sock\nthat the socket is still valid. Adjust conn->sk locking so it's\nprotected also by lock_sock() of the associated socket if any." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - sco_conn_ready runs from sco_connect_cfm via hci_connect_cfm on HCI Connection Complete, Synchronous Connection Complete, and deferred Connection Request for SCO/eSCO, driven by an in-range Bluetooth peer. Kernel CNA guidance classifies Bluetooth as Adjacent.\nAC:L - This is a use-after-free race between sco_conn_ready and sco_sock_release/sco_sock_kill. An attacker who times HCI SCO completion against socket close (rapid peer establish/teardown or concurrent connect/close) controls both sides and can retry until the window is hit; CONFIG_BT_BREDR defaults to y.\nPR:N - Incoming SCO is accepted when any listen socket exists (typical HFP/audio daemons on phones) with no Linux credentials required of the peer. sco_sock_create has no capability check, and listener close can occur from automatic bluetoothd/PipeWire teardown during connection setup.\nUI:N - No victim action is required at exploit time. OS Bluetooth audio stacks keep SCO listeners and manage sockets during normal headset, hands-free, and automotive operation while peer-initiated SCO/eSCO traffic is processed.\nS:U - The use-after-free corrupts in-kernel Bluetooth socket memory and can enable privilege escalation within the same host kernel security authority. It does not cross a VM, container, or IOMMU boundary.\nC:H - Use-after-free of struct sock after sco_sock_kill lets an attacker reclaim the freed slab object and read kernel memory through subsequent sock operations, which per CNA guidance is High confidentiality impact.\nI:H - sco_conn_ready writes sk->sk_state and makes an indirect call through sk->sk_state_change on the freed sock, a standard kernel heap UAF primitive for arbitrary write and control-flow hijack, scored High per UAF guidance.\nA:H - lock_sock and subsequent sk field access on a freed socket cause a kernel oops or panic. Per CNA guidance any use-after-free is High availability impact even before full exploitation." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/sco.c" ], "versions": [ { "version": "27c24fda62b601d6f9ca5e992502578c4310876f", "lessThan": "50aae396dc30377bec8e3b181b8346f8fd38f7d8", "status": "affected", "versionType": "git" }, { "version": "27c24fda62b601d6f9ca5e992502578c4310876f", "lessThan": "6e3840578aaad1a296aab1eaaa89ea3b7d5cbae1", "status": "affected", "versionType": "git" }, { "version": "27c24fda62b601d6f9ca5e992502578c4310876f", "lessThan": "d141d9b769bcd1b747898528c5023270cda040f2", "status": "affected", "versionType": "git" }, { "version": "27c24fda62b601d6f9ca5e992502578c4310876f", "lessThan": "73cb063f5ec6ca51eb1e246c6d332563002ac277", "status": "affected", "versionType": "git" }, { "version": "27c24fda62b601d6f9ca5e992502578c4310876f", "lessThan": "7199c78c3a3e399a4dc439d845826793880ccedc", "status": "affected", "versionType": "git" }, { "version": "27c24fda62b601d6f9ca5e992502578c4310876f", "lessThan": "4e37f6452d586b95c346a9abdd2fb80b67794f39", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/sco.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.212", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "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": "5.15", "versionEndExcluding": "5.15.212" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/50aae396dc30377bec8e3b181b8346f8fd38f7d8" }, { "url": "https://git.kernel.org/stable/c/6e3840578aaad1a296aab1eaaa89ea3b7d5cbae1" }, { "url": "https://git.kernel.org/stable/c/d141d9b769bcd1b747898528c5023270cda040f2" }, { "url": "https://git.kernel.org/stable/c/73cb063f5ec6ca51eb1e246c6d332563002ac277" }, { "url": "https://git.kernel.org/stable/c/7199c78c3a3e399a4dc439d845826793880ccedc" }, { "url": "https://git.kernel.org/stable/c/4e37f6452d586b95c346a9abdd2fb80b67794f39" } ], "title": "Bluetooth: SCO: hold sk properly in sco_conn_ready", "x_generator": { "engine": "bippy-1.2.0" } } } }