{"cve":"CVE-2026-31500","nvd":{"published":"2026-04-22T14:16:48.427","modified":"2026-10-15T02:19:08.743","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock\n\nbtintel_hw_error() issues two __hci_cmd_sync() calls (HCI_OP_RESET\nand Intel exception-info retrieval) without holding\nhci_req_sync_lock().  This lets it race against\nhci_dev_do_close() -> btintel_shutdown_combined(), which also runs\n__hci_cmd_sync() under the same lock.  When both paths manipulate\nhdev->req_status/req_rsp concurrently, the close path may free the\nresponse skb first, and the still-running hw_error path hits a\nslab-use-after-free in kfree_skb().\n\nWrap the whole recovery sequence in hci_req_sync_lock/unlock so it\nis serialized with every other synchronous HCI command issuer.\n\nBelow is the data race report and the kasan report:\n\n  BUG: data-race in __hci_cmd_sync_sk / btintel_shutdown_combined\n\n  read of hdev->req_rsp at net/bluetooth/hci_sync.c:199\n  by task kworker/u17:1/83:\n   __hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200\n   __hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223\n   btintel_hw_error+0x114/0x670 drivers/bluetooth/btintel.c:254\n   hci_error_reset+0x348/0xa30 net/bluetooth/hci_core.c:1030\n\n  write/free by task ioctl/22580:\n   btintel_shutdown_combined+0xd0/0x360\n    drivers/bluetooth/btintel.c:3648\n   hci_dev_close_sync+0x9ae/0x2c10 net/bluetooth/hci_sync.c:5246\n   hci_dev_do_close+0x232/0x460 net/bluetooth/hci_core.c:526\n\n  BUG: KASAN: slab-use-after-free in\n   sk_skb_reason_drop+0x43/0x380 net/core/skbuff.c:1202\n  Read of size 4 at addr ffff888144a738dc\n  by task kworker/u17:1/83:\n   __hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200\n   __hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223\n   btintel_hw_error+0x186/0x670 drivers/bluetooth/btintel.c:260","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/5f84e845648dfa86e42de5487f1a774b42f0444d","https://git.kernel.org/stable/c/66696648af477dc87859e5e4b607112f5f29d010","https://git.kernel.org/stable/c/7e041d0aad1d4d43d921ace052e04f4e2cacaed3","https://git.kernel.org/stable/c/94d8e6fe5d0818e9300e514e095a200bd5ff93ae","https://git.kernel.org/stable/c/e10a4cb72468686ffbe8bb2b0520e37f6be1a0c5"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:30:49.762551342+00:00"},"epss":{"cve":"CVE-2026-31500","score":0.00126,"percentile":0.02242,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}