{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-68304","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-12-16T14:48:05.294Z","datePublished":"2025-12-16T15:06:21.887Z","dateUpdated":"2026-05-11T21:50:34.921Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T21:50:34.921Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: lookup hci_conn on RX path on protocol side\n\nThe hdev lock/lookup/unlock/use pattern in the packet RX path doesn't\nensure hci_conn* is not concurrently modified/deleted. This locking\nappears to be leftover from before conn_hash started using RCU\ncommit bf4c63252490b (\"Bluetooth: convert conn hash to RCU\")\nand not clear if it had purpose since then.\n\nCurrently, there are code paths that delete hci_conn* from elsewhere\nthan the ordered hdev->workqueue where the RX work runs in. E.g.\ncommit 5af1f84ed13a (\"Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync\")\nintroduced some of these, and there probably were a few others before\nit.  It's better to do the locking so that even if these run\nconcurrently no UAF is possible.\n\nMove the lookup of hci_conn and associated socket-specific conn to\nprotocol recv handlers, and do them within a single critical section\nto cover hci_conn* usage and lookup.\n\nsyzkaller has reported a crash that appears to be this issue:\n\n    [Task hdev->workqueue]          [Task 2]\n                                    hci_disconnect_all_sync\n    l2cap_recv_acldata(hcon)\n                                      hci_conn_get(hcon)\n                                      hci_abort_conn_sync(hcon)\n                                        hci_dev_lock\n      hci_dev_lock\n                                        hci_conn_del(hcon)\n      v-------------------------------- hci_dev_unlock\n                                      hci_conn_put(hcon)\n      conn = hcon->l2cap_data (UAF)"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/bluetooth/hci_core.h","net/bluetooth/hci_core.c","net/bluetooth/iso.c","net/bluetooth/l2cap_core.c","net/bluetooth/sco.c"],"versions":[{"version":"5af1f84ed13a416297ab9ced7537f4d5ae7f329a","lessThan":"ec74cdf77310c43b01b83ee898a9bd4b4b0b8e93","status":"affected","versionType":"git"},{"version":"5af1f84ed13a416297ab9ced7537f4d5ae7f329a","lessThan":"79a2d4678ba90bdba577dc3af88cc900d6dcd5ee","status":"affected","versionType":"git"},{"version":"cd55c13bbb3d093ae601aa97e588ed4c1390ebb1","status":"affected","versionType":"git"},{"version":"4d3ca4a9aaf0aa798a6be372dc0fc3a29e37dd57","status":"affected","versionType":"git"},{"version":"80265dd1d944c3f33e52375b5dbe654980bd2688","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/bluetooth/hci_core.h","net/bluetooth/hci_core.c","net/bluetooth/iso.c","net/bluetooth/l2cap_core.c","net/bluetooth/sco.c"],"versions":[{"version":"6.6","status":"affected"},{"version":"0","lessThan":"6.6","status":"unaffected","versionType":"semver"},{"version":"6.17.11","lessThanOrEqual":"6.17.*","status":"unaffected","versionType":"semver"},{"version":"6.18","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":"6.6","versionEndExcluding":"6.17.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.149"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.5.3"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/ec74cdf77310c43b01b83ee898a9bd4b4b0b8e93"},{"url":"https://git.kernel.org/stable/c/79a2d4678ba90bdba577dc3af88cc900d6dcd5ee"}],"title":"Bluetooth: hci_core: lookup hci_conn on RX path on protocol side","x_generator":{"engine":"bippy-1.2.0"}}}}