In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: eir: Fix stack OOB write when prepending the Flags AD
eir_create_adv_data() builds the advertising data into a fixed-size
buffer ("size", 31 for the legacy path). It may prepend a 3-byte "Flags"
AD structure (LE_AD_NO_BREDR on an LE-only controller) and then copies
the per-instance data without checking that it still fits:
memcpy(ptr, adv->adv_data, adv->adv_data_len);
tlv_data_max_len() only reserves those 3 bytes when the user-supplied
flags carry a managed-flags bit, so an instance added with flags == 0 is
accepted with adv_data_len up to the full buffer. At advertise time the
flags are still prepended, and the memcpy() writes 3 + adv_data_len
bytes into the size-byte buffer:
BUG: KASAN: stack-out-of-bounds in eir_create_adv_data (net/bluetooth/eir.c:301)
Write of size 31 at addr ffff88800a547bdc by task kworker/u9:0/65
Workqueue: hci0 hci_cmd_sync_work
__asan_memcpy (mm/kasan/shadow.c:106)
eir_create_adv_data (net/bluetooth/eir.c:301)
hci_update_adv_data_sync (net/bluetooth/hci_sync.c:1310)
hci_schedule_adv_instance_sync (net/bluetooth/hci_sync.c:1817)
hci_cmd_sync_work (net/bluetooth/hci_sync.c:332)
This frame has 1 object:
[32, 64) 'cp'
The "Flags" structure is added by the kernel, not requested by
userspace, so only prepend it when it fits together with the instance
advertising data; when there is no room for both, drop the flags rather
than the user-provided data.
Reachable by a local user with CAP_NET_ADMIN owning an LE-only
controller on the legacy advertising path.
References
Configurations
Configuration 1 (hide)
|
History
13 Nov 2026, 18:27
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Linux linux Kernel
Linux |
|
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| References | () https://git.kernel.org/stable/c/09301f1fdf2aef8cce34d0c4650c30e7edb1ced9 - Patch | |
| References | () https://git.kernel.org/stable/c/0f0b6232af56441d0a2dcb173cc4f8d8aab39014 - Patch | |
| References | () https://git.kernel.org/stable/c/57077eeb586c42f124bc09e018449362223067b3 - Patch | |
| References | () https://git.kernel.org/stable/c/6f5fb689fdf80bdd143f22a502f9eb1f3c85e286 - Patch | |
| References | () https://git.kernel.org/stable/c/9174992ee1045c9c96e53eecda64f49dd7e8fbba - Patch | |
| References | () https://git.kernel.org/stable/c/f1b4df9c260c51726da2e86e19322825fddeefd0 - Patch |
21 Oct 2026, 13:19
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
19 Oct 2026, 21:17
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-121 |
Information
Published : 2026-07-27 21:17
Updated : 2026-11-13 18:27
NVD link : CVE-2026-64539
Mitre link : CVE-2026-64539
CVE.ORG link : CVE-2026-64539
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-121
Stack-based Buffer Overflow