Linux Kernel up to 7.2-rc4 hci_sync hci_cmd_sync_work use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k1.07+

Summaryinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. The affected element is the function hci_cmd_sync_work of the component hci_sync. Such manipulation leads to use after free. This vulnerability is documented as CVE-2026-68189. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4 and classified as very critical. Affected by this issue is the function hci_cmd_sync_work of the component hci_sync. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: Protect UUID list traversal The hci_sync conversion moved class-of-device and EIR generation from an HCI request built under hdev->lock to asynchronous command sync work. The worker holds hdev->req_lock, but that lock does not serialize access to hdev->uuids against add_uuid() and remove_uuid(), which update the list under hdev->lock. The following interleaving can therefore occur: CPU0 (command sync work) CPU1 (management socket) fetch uuid from the list list_del(&uuid->list) kfree(uuid) read uuid->size KASAN reports the resulting use-after-free: BUG: KASAN: slab-use-after-free in eir_create+0xb8f/0xee0 Read of size 1 at addr ffff88810dbd8620 by task kworker/u17:0/87 Workqueue: hci0 hci_cmd_sync_work Call Trace: eir_create+0xb8f/0xee0 hci_update_eir_sync+0x1c0/0x330 hci_cmd_sync_work+0x13c/0x290 process_one_work+0x63a/0x1070 worker_thread+0x45b/0xd10 Allocated by task 86: __kasan_kmalloc+0x8f/0xa0 add_uuid+0x18a/0x4b0 hci_sock_sendmsg+0x1033/0x1ea0 Freed by task 92: __kasan_slab_free+0x43/0x70 kfree+0x131/0x3c0 remove_uuid+0x25e/0x560 hci_sock_sendmsg+0x1033/0x1ea0 Hold hdev->lock while generating and committing the class-of-device and EIR snapshots. Release it before sending an HCI command, so controller waits do not happen under the device lock. This protects all UUID list walks in these paths and restores the serialization lost in the command sync conversion.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-68189 since 07/30/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 08/10/2026).

Upgrading to version 6.6.148, 6.12.101, 6.18.42, 7.1.6 or 7.2-rc5 eliminates this vulnerability. Applying the patch e4fa2c5c261d736b8e58759fdef3a968d510630c/a351f68fb24828b23a971e00b8238ee0e8a40380/a42f5536ea9c00e13f0c0fbb330feed95e2365ca/fe13adc258df88d95789e5673c7ba5178b5f8b28/e9027ffbf5a0f3c12ca8900822e884eae9f0821b is able to eliminate this problem.

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Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.148/6.12.101/6.18.42/7.1.6/7.2-rc5
Patch: e4fa2c5c261d736b8e58759fdef3a968d510630c/a351f68fb24828b23a971e00b8238ee0e8a40380/a42f5536ea9c00e13f0c0fbb330feed95e2365ca/fe13adc258df88d95789e5673c7ba5178b5f8b28/e9027ffbf5a0f3c12ca8900822e884eae9f0821b

Timelineinfo

07/30/2026 CVE reserved
08/10/2026 +11 days Advisory disclosed
08/10/2026 +0 days VulDB entry created
08/10/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-68189 (🔒)
GCVE (CVE): GCVE-0-2026-68189
GCVE (VulDB): GCVE-100-387536

Entryinfo

Created: 08/10/2026 15:54
Changes: 08/10/2026 15:54 (59)
Complete: 🔍
Cache ID: 216::103

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