Linux Kernel up to 6.12.95/6.18.38/7.1.3/7.2-rc2 Bluetooth ISO iso_conn_big_sync null pointer dereference

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6.0	$0-$5k	1.55-

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.95/6.18.38/7.1.3/7.2-rc2 and classified as critical. Affected is the function iso_conn_big_sync of the component Bluetooth ISO. The manipulation results in null pointer dereference. This vulnerability is cataloged as CVE-2026-64404. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.95/6.18.38/7.1.3/7.2-rc2. Affected is the function iso_conn_big_sync of the component Bluetooth ISO. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync() iso_conn_big_sync() drops the socket lock to call hci_get_route() and then re-acquires it, but dereferences iso_pi(sk)->conn->hcon afterwards without re-checking that conn is still valid. While the lock is dropped, the connection can be torn down under the same socket lock: iso_disconn_cfm() -> iso_conn_del() -> iso_chan_del() sets iso_pi(sk)->conn to NULL (and the broadcast teardown path can also clear conn->hcon on its own). When iso_conn_big_sync() re-acquires the lock and reads conn->hcon, conn may be NULL, causing a NULL pointer dereference (hcon is the first member of struct iso_conn). This path is reached from iso_sock_recvmsg() for a PA-sync broadcast sink socket (BT_SK_DEFER_SETUP | BT_SK_PA_SYNC), so the dropped-lock window can race with connection teardown driven by controller events. Re-validate iso_pi(sk)->conn and its hcon after re-acquiring the socket lock and bail out if the connection went away, as already done in the sibling iso_sock_rebind_bc().

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-64404 since 07/19/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/25/2026).

Upgrading to version 6.12.96, 6.18.39, 7.1.4 or 7.2-rc3 eliminates this vulnerability. Applying the patch b3e647a4aa4d2d054f86a783f5c426035e1dc237/b84eeb7636d6962dd882d5e0b31475e4f404313c/01afd198c2c286cd3b81f44d4e33a2e638711550/d5541eb148da72d5e0a1bca8ecd171f9fc8b366f is able to eliminate this problem.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
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• 6.12.90
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• 6.12.93
• 6.12.94
• 6.12.95
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
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• 6.18.36
• 6.18.37
• 6.18.38
• 7.1.0
• 7.1.1
• 7.1.2
• 7.1.3
• 7.2-rc1
• 7.2-rc2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.12.96/6.18.39/7.1.4/7.2-rc3
Patch: b3e647a4aa4d2d054f86a783f5c426035e1dc237/b84eeb7636d6962dd882d5e0b31475e4f404313c/01afd198c2c286cd3b81f44d4e33a2e638711550/d5541eb148da72d5e0a1bca8ecd171f9fc8b366f

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64404 (🔒)
GCVE (CVE): GCVE-0-2026-64404
GCVE (VulDB): GCVE-100-383184

Entryinfo

Created: 07/25/2026 18:17
Changes: 07/25/2026 18:17 (59)
Complete: 🔍
Cache ID: 216::103

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Discussion

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