{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53357", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.400Z", "datePublished": "2026-07-02T13:43:17.077Z", "dateUpdated": "2026-08-05T12:35:06.665Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:35:06.665Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del()\n\nbt_accept_dequeue() unlinks a not-yet-accepted child from the parent\naccept queue and release_sock()s it before returning, so the returned\nsk has no caller reference and is unlocked.\n\nl2cap_sock_cleanup_listen() walks these children on listening-socket\nclose. A concurrent HCI disconnect drives hci_rx_work ->\nl2cap_conn_del() which runs l2cap_chan_del() + l2cap_sock_kill() and\nfrees the child sk and its l2cap_chan; cleanup_listen() then uses both:\n\n BUG: KASAN: slab-use-after-free in l2cap_sock_kill\n l2cap_sock_kill / l2cap_sock_cleanup_listen / __x64_sys_close\n Freed by: l2cap_conn_del -> l2cap_sock_close_cb -> l2cap_sock_kill\n\nThis is distinct from the two fixes already in this area: commit\ne83f5e24da741 (\"Bluetooth: serialize accept_q access\") serialises the\naccept_q list/poll and takes temporary refs inside bt_accept_dequeue(),\nand CVE-2025-39860 serialises the userspace close()/accept() race by\ncalling cleanup_listen() under lock_sock() in l2cap_sock_release().\nNeither covers l2cap_conn_del() running from hci_rx_work, so this UAF\nstill reproduces on current bluetooth/master.\n\nTake the reference at the source: bt_accept_dequeue() does sock_hold()\nwhile sk is still locked, before release_sock(); callers sock_put().\ncleanup_listen() pins the chan with l2cap_chan_hold_unless_zero() under\na brief child sk lock (serialising vs l2cap_sock_teardown_cb()), drops\nit before l2cap_chan_lock(), and skips a duplicate l2cap_sock_kill() on\nSOCK_DEAD. conn->lock is not taken here: cleanup_listen() runs under\nthe parent sk lock and that would invert\nconn->lock -> chan->lock -> sk_lock (lockdep).\n\nKASAN/SMP: an unprivileged listen/close vs HCI-disconnect race produced\n12 use-after-free reports per run before this change; 0, and no lockdep\nreport, over 1600+ raced iterations after it on bluetooth/master." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - The race is driven through Bluetooth L2CAP/HCI connection and disconnect handling from a nearby peer, so it is limited to Bluetooth-adjacent reachability rather than routable network access. The local listener/close side is accounted for in PR.\nAC:L - This is a race, but the attacker can reasonably control the listener close timing and the Bluetooth peer disconnect timing. The commit reports reliable unprivileged raced iterations, so no uncontrollable condition is required.\nPR:L - Creating, binding to a dynamic PSM, listening on, and closing non-raw L2CAP sockets does not require capabilities; only raw sockets or reserved PSMs need privileges. A basic unprivileged local user on the target can set up the vulnerable listener.\nUI:N - No victim user action is required once the attacker can run the unprivileged local setup and control the Bluetooth peer. The trigger is socket close racing HCI disconnect processing.\nS:U - The corruption is within the Linux kernel Bluetooth/socket subsystem and impacts the same kernel security authority. It is not a VM escape or cross-scope boundary bypass.\nC:H - The bug is a use-after-free of both the child sock and its l2cap_chan, and freed kernel heap objects can be reclaimed and used for disclosure primitives. Per kernel CVSS guidance, UAF memory corruption supports high confidentiality impact.\nI:H - The stale sock/channel pointers are used after l2cap_conn_del frees them, including through cleanup and kill paths, making heap grooming and control-flow or write-primitive exploitation plausible. Per guidance, UAF memory corruption supports high integrity impact.\nA:H - The observed failure is a KASAN slab-use-after-free in kernel Bluetooth cleanup, which can crash or oops the kernel. Repeated triggering can deny availability." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/af_bluetooth.c", "net/bluetooth/iso.c", "net/bluetooth/l2cap_sock.c", "net/bluetooth/rfcomm/sock.c", "net/bluetooth/sco.c" ], "versions": [ { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "751de6ec671fe75ad9cf65a0638d2a06b6a5984d", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "407217734835d21d4e0105ebf347860dc1806f88", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "7eebd4c2c86f573af87ff165d08a83432eb0b919", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "5d86d2f1b4d9a508c441d3e45277ae1a73cfed57", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "87c543e2f78d0871f271df92dab98901bbd5b6f5", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "added1213395071470a900cc845a042fb51882a6", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "a5ca86a6097a8b030ca3226cd300b17ed330f966", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "ab1513597c6cf17cd1ad2a21e3b045421b48e022", "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/af_bluetooth.c", "net/bluetooth/iso.c", "net/bluetooth/l2cap_sock.c", "net/bluetooth/rfcomm/sock.c", "net/bluetooth/sco.c" ], "versions": [ { "version": "5.7", "status": "affected" }, { "version": "0", "lessThan": "5.7", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.259", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.142", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.92", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.34", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.11", "lessThanOrEqual": "7.0.*", "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": "5.7", "versionEndExcluding": "5.10.259" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.6.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.12.92" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.18.34" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.0.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/751de6ec671fe75ad9cf65a0638d2a06b6a5984d" }, { "url": "https://git.kernel.org/stable/c/407217734835d21d4e0105ebf347860dc1806f88" }, { "url": "https://git.kernel.org/stable/c/7eebd4c2c86f573af87ff165d08a83432eb0b919" }, { "url": "https://git.kernel.org/stable/c/5d86d2f1b4d9a508c441d3e45277ae1a73cfed57" }, { "url": "https://git.kernel.org/stable/c/87c543e2f78d0871f271df92dab98901bbd5b6f5" }, { "url": "https://git.kernel.org/stable/c/added1213395071470a900cc845a042fb51882a6" }, { "url": "https://git.kernel.org/stable/c/a5ca86a6097a8b030ca3226cd300b17ed330f966" }, { "url": "https://git.kernel.org/stable/c/ab1513597c6cf17cd1ad2a21e3b045421b48e022" } ], "title": "Bluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del()", "x_generator": { "engine": "bippy-1.2.0" } } } }