GHSA-5243-P4QJ-J66V
Vulnerability from github – Published: 2026-07-19 15:30 – Updated: 2026-07-19 15:30In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: Fix data-race on iso_pi fields in hci_get_route calls
iso_connect_bis(), iso_connect_cis(), iso_listen_bis(), and iso_conn_big_sync() call hci_get_route() using iso_pi(sk)->dst, iso_pi(sk)->src, and iso_pi(sk)->src_type without holding lock_sock().
These fields may be modified concurrently by connect() or setsockopt() on the same socket, resulting in data-races reported by KCSAN.
Fix this by snapshotting the required fields under lock_sock() before calling hci_get_route().
BUG: KCSAN: data-race in memcmp+0x45/0xb0
race at unknown origin, with read to 0xffff8880122135cf of 1 bytes by task 333 on cpu 1: memcmp+0x45/0xb0 hci_get_route+0x27e/0x490 iso_connect_cis+0x4c/0xa10 iso_sock_connect+0x60e/0xb30 __sys_connect_file+0xbd/0xe0 __sys_connect+0xe0/0x110 __x64_sys_connect+0x40/0x50 x64_sys_call+0xcad/0x1c60 do_syscall_64+0x133/0x590 entry_SYSCALL_64_after_hwframe+0x77/0x7f
{
"affected": [],
"aliases": [
"CVE-2026-63871"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-19T15:16:54Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: Fix data-race on iso_pi fields in hci_get_route calls\n\niso_connect_bis(), iso_connect_cis(), iso_listen_bis(), and\niso_conn_big_sync() call hci_get_route() using iso_pi(sk)-\u003edst,\niso_pi(sk)-\u003esrc, and iso_pi(sk)-\u003esrc_type without holding lock_sock().\n\nThese fields may be modified concurrently by connect() or setsockopt()\non the same socket, resulting in data-races reported by KCSAN.\n\nFix this by snapshotting the required fields under lock_sock() before\ncalling hci_get_route().\n\nBUG: KCSAN: data-race in memcmp+0x45/0xb0\n\nrace at unknown origin, with read to 0xffff8880122135cf of 1 bytes\nby task 333 on cpu 1:\n memcmp+0x45/0xb0\n hci_get_route+0x27e/0x490\n iso_connect_cis+0x4c/0xa10\n iso_sock_connect+0x60e/0xb30\n __sys_connect_file+0xbd/0xe0\n __sys_connect+0xe0/0x110\n __x64_sys_connect+0x40/0x50\n x64_sys_call+0xcad/0x1c60\n do_syscall_64+0x133/0x590\n entry_SYSCALL_64_after_hwframe+0x77/0x7f",
"id": "GHSA-5243-p4qj-j66v",
"modified": "2026-07-19T15:30:28Z",
"published": "2026-07-19T15:30:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63871"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/859bb1f4cb615d98c9c1ab2bd76ebb0b8fe46020"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9798f7d41d85ff763afd1f1cc0533b5c416c8348"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9ca7053d6215d89c33f28893bfd1625a32919d3f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ab84fd7779a2a7ff5d2c8eac212c43733f56216e"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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