{"id":"CVE-2026-64404","state":"PUBLISHED","title":"Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()\n\niso_conn_big_sync() drops the socket lock to call hci_get_route() and\nthen re-acquires it, but dereferences iso_pi(sk)->conn->hcon afterwards\nwithout re-checking that conn is still valid.\n\nWhile the lock is dropped, the connection can be torn down under the\nsame socket lock: iso_disconn_cfm() -> iso_conn_del() -> iso_chan_del()\nsets iso_pi(sk)->conn to NULL (and the broadcast teardown path can also\nclear conn->hcon on its own). When iso_conn_big_sync() re-acquires the\nlock and reads conn->hcon, conn may be NULL, causing a NULL pointer\ndereference (hcon is the first member of struct iso_conn).\n\nThis path is reached from iso_sock_recvmsg() for a PA-sync broadcast\nsink socket (BT_SK_DEFER_SETUP | BT_SK_PA_SYNC), so the dropped-lock\nwindow can race with connection teardown driven by controller events.\n\nRe-validate iso_pi(sk)->conn and its hcon after re-acquiring the socket\nlock and bail out if the connection went away, as already done in the\nsibling iso_sock_rebind_bc().","publishedAt":"2026-07-25T08:50:46.523Z","updatedAt":"2026-08-17T04:55:02.350Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"cbe640d6cae590b9a7d81ce86fe9a90e83eec1d5","status":"affected","lessThan":"b3e647a4aa4d2d054f86a783f5c426035e1dc237","versionType":"git"},{"version":"7a17308c17880d259105f6e591eb1bc77b9612f0","status":"affected","lessThan":"b84eeb7636d6962dd882d5e0b31475e4f404313c","versionType":"git"},{"version":"7a17308c17880d259105f6e591eb1bc77b9612f0","status":"affected","lessThan":"01afd198c2c286cd3b81f44d4e33a2e638711550","versionType":"git"},{"version":"7a17308c17880d259105f6e591eb1bc77b9612f0","status":"affected","lessThan":"d5541eb148da72d5e0a1bca8ecd171f9fc8b366f","versionType":"git"},{"version":"6.12.6","status":"affected","lessThan":"6.12.96","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/iso.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.12.96","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/iso.c"]}],"references":["https://git.kernel.org/stable/c/b3e647a4aa4d2d054f86a783f5c426035e1dc237","https://git.kernel.org/stable/c/b84eeb7636d6962dd882d5e0b31475e4f404313c","https://git.kernel.org/stable/c/01afd198c2c286cd3b81f44d4e33a2e638711550","https://git.kernel.org/stable/c/d5541eb148da72d5e0a1bca8ecd171f9fc8b366f"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64404.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64404","state":"PUBLISHED","datePublished":"2026-07-25T08:50:46.523Z","dateUpdated":"2026-08-17T04:55:02.350Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.785Z"},"containers":{"cna":{"title":"Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()\n\niso_conn_big_sync() drops the socket lock to call hci_get_route() and\nthen re-acquires it, but dereferences iso_pi(sk)->conn->hcon afterwards\nwithout re-checking that conn is still valid.\n\nWhile the lock is dropped, the connection can be torn down under the\nsame socket lock: iso_disconn_cfm() -> iso_conn_del() -> iso_chan_del()\nsets iso_pi(sk)->conn to NULL (and the broadcast teardown path can also\nclear conn->hcon on its own). When iso_conn_big_sync() re-acquires the\nlock and reads conn->hcon, conn may be NULL, causing a NULL pointer\ndereference (hcon is the first member of struct iso_conn).\n\nThis path is reached from iso_sock_recvmsg() for a PA-sync broadcast\nsink socket (BT_SK_DEFER_SETUP | BT_SK_PA_SYNC), so the dropped-lock\nwindow can race with connection teardown driven by controller events.\n\nRe-validate iso_pi(sk)->conn and its hcon after re-acquiring the socket\nlock and bail out if the connection went away, as already done in the\nsibling iso_sock_rebind_bc()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"cbe640d6cae590b9a7d81ce86fe9a90e83eec1d5","status":"affected","lessThan":"b3e647a4aa4d2d054f86a783f5c426035e1dc237","versionType":"git"},{"version":"7a17308c17880d259105f6e591eb1bc77b9612f0","status":"affected","lessThan":"b84eeb7636d6962dd882d5e0b31475e4f404313c","versionType":"git"},{"version":"7a17308c17880d259105f6e591eb1bc77b9612f0","status":"affected","lessThan":"01afd198c2c286cd3b81f44d4e33a2e638711550","versionType":"git"},{"version":"7a17308c17880d259105f6e591eb1bc77b9612f0","status":"affected","lessThan":"d5541eb148da72d5e0a1bca8ecd171f9fc8b366f","versionType":"git"},{"version":"6.12.6","status":"affected","lessThan":"6.12.96","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/iso.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.12.96","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/iso.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/b3e647a4aa4d2d054f86a783f5c426035e1dc237"},{"url":"https://git.kernel.org/stable/c/b84eeb7636d6962dd882d5e0b31475e4f404313c"},{"url":"https://git.kernel.org/stable/c/01afd198c2c286cd3b81f44d4e33a2e638711550"},{"url":"https://git.kernel.org/stable/c/d5541eb148da72d5e0a1bca8ecd171f9fc8b366f"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:55:02.350Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.6","versionEndExcluding":"6.12.96"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.18.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.1.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}