{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89569", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.726Z", "datePublished": "2026-09-11T19:44:38.838Z", "dateUpdated": "2026-10-19T08:49:02.628Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:49:02.628Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: serialize security confirmation handling\n\nrfcomm_security_cfm() looks up a session on session_list and then walks\nits DLC list without holding rfcomm_mutex. Since RFCOMM session teardown\nuses rfcomm_mutex, krfcommd can close and free the same session and DLCs\nconcurrently:\n\n hci_rx_work krfcommd\n ----------- ---------\n rfcomm_session_get()\n rfcomm_lock()\n rfcomm_session_close()\n rfcomm_dlc_unlink()\n rfcomm_session_del()\n kfree(s)\n rfcomm_unlock()\n walk s->dlcs\n\nThe callback can then read a freed session list head and touch freed DLCs\nwhile updating their flags or timers.\n\nSerialize the session lookup and DLC traversal in rfcomm_security_cfm()\nwith rfcomm_mutex. This matches the existing RFCOMM session lifetime\nrules and prevents concurrent rfcomm_session_del() / rfcomm_dlc_unlink()\nfrom tearing the objects down while the callback is using them.\n\nKASAN reported:\n\n BUG: KASAN: slab-use-after-free in rfcomm_security_cfm+0x41c/0x440\n Read of size 8 at addr ffff888111fb3960 by task kworker/u17:1/89\n Workqueue: hci0 hci_rx_work\n Call Trace:\n rfcomm_security_cfm+0x41c/0x440\n hci_encrypt_cfm+0x139/0x590\n hci_encrypt_change_evt+0x37b/0xc40\n hci_event_packet+0x71b/0xb20\n hci_rx_work+0x293/0x730\n Allocated by task 69:\n rfcomm_session_add+0x9e/0x2f0\n rfcomm_run+0x44b/0x41e0\n Freed by task 69:\n kfree+0x131/0x3c0\n rfcomm_session_del+0x188/0x220\n rfcomm_run+0x1985/0x41e0" } ], "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 - rfcomm_security_cfm() runs from hci_encrypt_cfm()/hci_auth_cfm() on hci_rx_work when the controller reports encryption or authentication complete. An in-range Bluetooth peer that opens an RFCOMM/L2CAP session can drive those HCI events; kernel CNA guidance scores Bluetooth as Adjacent.\nAC:L - The UAF is a race between hci_rx_work walking the session and krfcommd freeing it. A peer controls both sides by triggering encrypt/auth complete while disconnecting RFCOMM/L2CAP or the ACL link so krfcommd runs rfcomm_session_close(), and can retry until the window is hit.\nPR:N - A nearby Bluetooth device needs no Linux account or capability. krfcommd listens on L2CAP PSM RFCOMM at default BT_SECURITY_LOW, and HCI encrypt/auth complete (including failures) call rfcomm_security_cfm() with no local credential check.\nUI:N - Phones, cars, and IoT devices with Bluetooth enabled accept RFCOMM/L2CAP and emit encrypt-change events during ordinary link setup or teardown. No extra victim action such as pairing confirmation, mounting, or opening a file is required at exploit time.\nS:U - The UAF corrupts kernel RFCOMM session and DLC objects in the host Bluetooth stack. It does not cross a VM, IOMMU, or other security-authority boundary.\nC:H - After rfcomm_session_del() frees the session, the callback reads the slab-freed list head and DLC flags, state, and sec_level. Kernel UAF of these objects enables heap reuse and arbitrary kernel read primitives.\nI:H - The callback writes DLC flag bits and arms or cancels DLC timers on objects krfcommd may already have unlinked and freed, so a reused slab object can be corrupted or have its timer hijacked for control-flow takeover.\nA:H - KASAN reported slab-use-after-free in rfcomm_security_cfm() on hci_rx_work; triggering the race oopses or panics the kernel even without a full exploit." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/rfcomm/core.c" ], "versions": [ { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "62ce8b33eb238cf18c15207332fbdc26d858f592", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "3873f3449701b3dc98cba577923be6493598e7a1", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "7ded3264106418c6456ccceaafd9fda596ce12c3", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "82425b14f0fb22e46cfddc56d6465570f5ed0ce6", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "1b7841ffad08e911e8c4b9470f3fa08423568940", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "946d76db77ee5f922968ce558629ae47b381e3fc", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "fbf7961964a6e93360179f64712320ae9a1e9577", "status": "affected", "versionType": "git" }, { "version": "08c30aca9e698faddebd34f81e1196295f9dc063", "lessThan": "759c185d0bbdb131357408f50b8735e04ed3caff", "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/rfcomm/core.c" ], "versions": [ { "version": "3.10", "status": "affected" }, { "version": "0", "lessThan": "3.10", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "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": "3.10", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/62ce8b33eb238cf18c15207332fbdc26d858f592" }, { "url": "https://git.kernel.org/stable/c/3873f3449701b3dc98cba577923be6493598e7a1" }, { "url": "https://git.kernel.org/stable/c/7ded3264106418c6456ccceaafd9fda596ce12c3" }, { "url": "https://git.kernel.org/stable/c/82425b14f0fb22e46cfddc56d6465570f5ed0ce6" }, { "url": "https://git.kernel.org/stable/c/1b7841ffad08e911e8c4b9470f3fa08423568940" }, { "url": "https://git.kernel.org/stable/c/946d76db77ee5f922968ce558629ae47b381e3fc" }, { "url": "https://git.kernel.org/stable/c/fbf7961964a6e93360179f64712320ae9a1e9577" }, { "url": "https://git.kernel.org/stable/c/759c185d0bbdb131357408f50b8735e04ed3caff" } ], "title": "Bluetooth: RFCOMM: serialize security confirmation handling", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-89569", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:24:18.874687Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:44.485Z" } } ] } }