{"api_version":"1","generated_at":"2026-05-01T19:27:28+00:00","cve":"CVE-2026-43023","urls":{"html":"https://cve.report/CVE-2026-43023","api":"https://cve.report/api/cve/CVE-2026-43023.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43023","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43023"},"summary":{"title":"Bluetooth: SCO: fix race conditions in sco_sock_connect()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: SCO: fix race conditions in sco_sock_connect()\n\nsco_sock_connect() checks sk_state and sk_type without holding\nthe socket lock. Two concurrent connect() syscalls on the same\nsocket can both pass the check and enter sco_connect(), leading\nto use-after-free.\n\nThe buggy scenario involves three participants and was confirmed\nwith additional logging instrumentation:\n\n Thread A (connect): HCI disconnect: Thread B (connect):\n\n sco_sock_connect(sk) sco_sock_connect(sk)\n sk_state==BT_OPEN sk_state==BT_OPEN\n (pass, no lock) (pass, no lock)\n sco_connect(sk): sco_connect(sk):\n hci_dev_lock hci_dev_lock\n hci_connect_sco <- blocked\n -> hcon1\n sco_conn_add->conn1\n lock_sock(sk)\n sco_chan_add:\n conn1->sk = sk\n sk->conn = conn1\n sk_state=BT_CONNECT\n release_sock\n hci_dev_unlock\n hci_dev_lock\n sco_conn_del:\n lock_sock(sk)\n sco_chan_del:\n sk->conn=NULL\n conn1->sk=NULL\n sk_state=\n BT_CLOSED\n SOCK_ZAPPED\n release_sock\n hci_dev_unlock\n (unblocked)\n hci_connect_sco\n -> hcon2\n sco_conn_add\n -> conn2\n lock_sock(sk)\n sco_chan_add:\n sk->conn=conn2\n sk_state=\n BT_CONNECT\n // zombie sk!\n release_sock\n hci_dev_unlock\n\nThread B revives a BT_CLOSED + SOCK_ZAPPED socket back to\nBT_CONNECT. Subsequent cleanup triggers double sock_put() and\nuse-after-free. Meanwhile conn1 is leaked as it was orphaned\nwhen sco_conn_del() cleared the association.\n\nFix this by:\n- Moving lock_sock() before the sk_state/sk_type checks in\n sco_sock_connect() to serialize concurrent connect attempts\n- Fixing the sk_type != SOCK_SEQPACKET check to actually\n return the error instead of just assigning it\n- Adding a state re-check in sco_connect() after lock_sock()\n to catch state changes during the window between the locks\n- Adding sco_pi(sk)->conn check in sco_chan_add() to prevent\n double-attach of a socket to multiple connections\n- Adding hci_conn_drop() on sco_chan_add failure to prevent\n HCI connection leaks","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-01 15:16:46","updated_at":"2026-05-01 15:24:14"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/dabf22269242e2f2bf44c43fcdc2fa763df7f9cc","name":"https://git.kernel.org/stable/c/dabf22269242e2f2bf44c43fcdc2fa763df7f9cc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/7e296ffdab5bdab718dff7c14288fdcb9154fa27","name":"https://git.kernel.org/stable/c/7e296ffdab5bdab718dff7c14288fdcb9154fa27","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/8a5b0135d4a5d9683203a3d9a12a711ccec5936b","name":"https://git.kernel.org/stable/c/8a5b0135d4a5d9683203a3d9a12a711ccec5936b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/98c8d3bfdaa657d8f472dbbebd7ea8cd816d8a8d","name":"https://git.kernel.org/stable/c/98c8d3bfdaa657d8f472dbbebd7ea8cd816d8a8d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/adb90cd0f9f7a8d438fcb93354040fbafc5ae2a0","name":"https://git.kernel.org/stable/c/adb90cd0f9f7a8d438fcb93354040fbafc5ae2a0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d002bd11024bd231bcb606877e33951ffb7bed14","name":"https://git.kernel.org/stable/c/d002bd11024bd231bcb606877e33951ffb7bed14","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43023","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43023","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 70a13b1e25fef37c87c8a1228ddb8900efbca7cf dabf22269242e2f2bf44c43fcdc2fa763df7f9cc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3 adb90cd0f9f7a8d438fcb93354040fbafc5ae2a0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3 7e296ffdab5bdab718dff7c14288fdcb9154fa27 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3 98c8d3bfdaa657d8f472dbbebd7ea8cd816d8a8d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3 d002bd11024bd231bcb606877e33951ffb7bed14 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3 8a5b0135d4a5d9683203a3d9a12a711ccec5936b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.3","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.3 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.168 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.134 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.81 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.22 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.12 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/bluetooth/sco.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"dabf22269242e2f2bf44c43fcdc2fa763df7f9cc","status":"affected","version":"70a13b1e25fef37c87c8a1228ddb8900efbca7cf","versionType":"git"},{"lessThan":"adb90cd0f9f7a8d438fcb93354040fbafc5ae2a0","status":"affected","version":"9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3","versionType":"git"},{"lessThan":"7e296ffdab5bdab718dff7c14288fdcb9154fa27","status":"affected","version":"9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3","versionType":"git"},{"lessThan":"98c8d3bfdaa657d8f472dbbebd7ea8cd816d8a8d","status":"affected","version":"9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3","versionType":"git"},{"lessThan":"d002bd11024bd231bcb606877e33951ffb7bed14","status":"affected","version":"9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3","versionType":"git"},{"lessThan":"8a5b0135d4a5d9683203a3d9a12a711ccec5936b","status":"affected","version":"9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/bluetooth/sco.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.3"},{"lessThan":"6.3","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.168","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.134","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.81","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.22","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.12","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.168","versionStartIncluding":"6.1.109","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.134","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.81","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.22","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.12","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"6.3","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: SCO: fix race conditions in sco_sock_connect()\n\nsco_sock_connect() checks sk_state and sk_type without holding\nthe socket lock. Two concurrent connect() syscalls on the same\nsocket can both pass the check and enter sco_connect(), leading\nto use-after-free.\n\nThe buggy scenario involves three participants and was confirmed\nwith additional logging instrumentation:\n\n Thread A (connect): HCI disconnect: Thread B (connect):\n\n sco_sock_connect(sk) sco_sock_connect(sk)\n sk_state==BT_OPEN sk_state==BT_OPEN\n (pass, no lock) (pass, no lock)\n sco_connect(sk): sco_connect(sk):\n hci_dev_lock hci_dev_lock\n hci_connect_sco <- blocked\n -> hcon1\n sco_conn_add->conn1\n lock_sock(sk)\n sco_chan_add:\n conn1->sk = sk\n sk->conn = conn1\n sk_state=BT_CONNECT\n release_sock\n hci_dev_unlock\n hci_dev_lock\n sco_conn_del:\n lock_sock(sk)\n sco_chan_del:\n sk->conn=NULL\n conn1->sk=NULL\n sk_state=\n BT_CLOSED\n SOCK_ZAPPED\n release_sock\n hci_dev_unlock\n (unblocked)\n hci_connect_sco\n -> hcon2\n sco_conn_add\n -> conn2\n lock_sock(sk)\n sco_chan_add:\n sk->conn=conn2\n sk_state=\n BT_CONNECT\n // zombie sk!\n release_sock\n hci_dev_unlock\n\nThread B revives a BT_CLOSED + SOCK_ZAPPED socket back to\nBT_CONNECT. Subsequent cleanup triggers double sock_put() and\nuse-after-free. Meanwhile conn1 is leaked as it was orphaned\nwhen sco_conn_del() cleared the association.\n\nFix this by:\n- Moving lock_sock() before the sk_state/sk_type checks in\n sco_sock_connect() to serialize concurrent connect attempts\n- Fixing the sk_type != SOCK_SEQPACKET check to actually\n return the error instead of just assigning it\n- Adding a state re-check in sco_connect() after lock_sock()\n to catch state changes during the window between the locks\n- Adding sco_pi(sk)->conn check in sco_chan_add() to prevent\n double-attach of a socket to multiple connections\n- Adding hci_conn_drop() on sco_chan_add failure to prevent\n HCI connection leaks"}],"providerMetadata":{"dateUpdated":"2026-05-01T14:15:25.736Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/dabf22269242e2f2bf44c43fcdc2fa763df7f9cc"},{"url":"https://git.kernel.org/stable/c/adb90cd0f9f7a8d438fcb93354040fbafc5ae2a0"},{"url":"https://git.kernel.org/stable/c/7e296ffdab5bdab718dff7c14288fdcb9154fa27"},{"url":"https://git.kernel.org/stable/c/98c8d3bfdaa657d8f472dbbebd7ea8cd816d8a8d"},{"url":"https://git.kernel.org/stable/c/d002bd11024bd231bcb606877e33951ffb7bed14"},{"url":"https://git.kernel.org/stable/c/8a5b0135d4a5d9683203a3d9a12a711ccec5936b"}],"title":"Bluetooth: SCO: fix race conditions in sco_sock_connect()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43023","datePublished":"2026-05-01T14:15:25.736Z","dateReserved":"2026-05-01T14:12:55.975Z","dateUpdated":"2026-05-01T14:15:25.736Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-01 15:16:46","lastModifiedDate":"2026-05-01 15:24:14","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43023","Ordinal":"1","Title":"Bluetooth: SCO: fix race conditions in sco_sock_connect()","CVE":"CVE-2026-43023","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43023","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: SCO: fix race conditions in sco_sock_connect()\n\nsco_sock_connect() checks sk_state and sk_type without holding\nthe socket lock. Two concurrent connect() syscalls on the same\nsocket can both pass the check and enter sco_connect(), leading\nto use-after-free.\n\nThe buggy scenario involves three participants and was confirmed\nwith additional logging instrumentation:\n\n Thread A (connect): HCI disconnect: Thread B (connect):\n\n sco_sock_connect(sk) sco_sock_connect(sk)\n sk_state==BT_OPEN sk_state==BT_OPEN\n (pass, no lock) (pass, no lock)\n sco_connect(sk): sco_connect(sk):\n hci_dev_lock hci_dev_lock\n hci_connect_sco <- blocked\n -> hcon1\n sco_conn_add->conn1\n lock_sock(sk)\n sco_chan_add:\n conn1->sk = sk\n sk->conn = conn1\n sk_state=BT_CONNECT\n release_sock\n hci_dev_unlock\n hci_dev_lock\n sco_conn_del:\n lock_sock(sk)\n sco_chan_del:\n sk->conn=NULL\n conn1->sk=NULL\n sk_state=\n BT_CLOSED\n SOCK_ZAPPED\n release_sock\n hci_dev_unlock\n (unblocked)\n hci_connect_sco\n -> hcon2\n sco_conn_add\n -> conn2\n lock_sock(sk)\n sco_chan_add:\n sk->conn=conn2\n sk_state=\n BT_CONNECT\n // zombie sk!\n release_sock\n hci_dev_unlock\n\nThread B revives a BT_CLOSED + SOCK_ZAPPED socket back to\nBT_CONNECT. Subsequent cleanup triggers double sock_put() and\nuse-after-free. Meanwhile conn1 is leaked as it was orphaned\nwhen sco_conn_del() cleared the association.\n\nFix this by:\n- Moving lock_sock() before the sk_state/sk_type checks in\n sco_sock_connect() to serialize concurrent connect attempts\n- Fixing the sk_type != SOCK_SEQPACKET check to actually\n return the error instead of just assigning it\n- Adding a state re-check in sco_connect() after lock_sock()\n to catch state changes during the window between the locks\n- Adding sco_pi(sk)->conn check in sco_chan_add() to prevent\n double-attach of a socket to multiple connections\n- Adding hci_conn_drop() on sco_chan_add failure to prevent\n HCI connection leaks","Type":"Description","Title":"Bluetooth: SCO: fix race conditions in sco_sock_connect()"}]}}}