Linux Kernel up to 7.2-rc3 isotp isotp_release use after free

CVSS Meta Temp Score
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CTI Interest Score
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9.5$5k-$25k1.01-

Summaryinfo

A vulnerability, which was classified as very critical, has been found in Linux Kernel up to 7.2-rc3. Affected by this issue is the function isotp_release of the component isotp. The manipulation leads to use after free. This vulnerability is referenced as CVE-2026-72126. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.2-rc3. It has been rated as very critical. This issue affects the function isotp_release of the component isotp. 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. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: can: isotp: use unconditional synchronize_rcu() in isotp_release() isotp_notify() unregisters the (RCU) CAN filters via can_rx_unregister() and clears so->bound without waiting for a grace period. isotp_release() uses so->bound to decide whether it needs to call synchronize_rcu() before cancelling so->rxtimer, so when NETDEV_UNREGISTER runs first it skips that synchronize_rcu() and can cancel the timer while an in-flight isotp_rcv() is still executing and about to re-arm it via isotp_send_fc(), leading to a use-after-free timer callback on the freed socket. sakisho-bot remarked a problem with rtnl_lock held in isotp_notify(), therefore make isotp_release() always call synchronize_rcu() before cancelling the timers, regardless of so->bound. This still closes the original race (isotp_notify() clearing so->bound without waiting for in-flight isotp_rcv() callers before isotp_release() cancels the RX timer) without adding any RCU wait to the netdevice notifier path.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-72126 since 08/09/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/15/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5 or 7.2-rc4 eliminates this vulnerability. Applying the patch 945d9894502cd9124f5d676181c542ed2000f7c0/59672aa4bcd8d32172c1ff6a179583981d6acabc/15413a082df69175c2f96aeab4c26fe1ff7cff03/6280eda96e0707264849fa7d036fed873c1f8a6d/cb6abc584a1bfab107ac003d64948a4aef1730aa/b88a511308779c225005d7994b8744561bdbafbc/b8278ff605187ef3fa0f2705e93251cce4c4f8ee/9b1a02e0d980ac6b0e36a90378f847062f81d7e4 is able to eliminate this problem.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
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

EPSS Score: 🔒
EPSS Percentile: 🔒

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 5.10.261/5.15.212/6.1.178/6.6.145/6.12.97/6.18.40/7.1.5/7.2-rc4
Patch: 945d9894502cd9124f5d676181c542ed2000f7c0/59672aa4bcd8d32172c1ff6a179583981d6acabc/15413a082df69175c2f96aeab4c26fe1ff7cff03/6280eda96e0707264849fa7d036fed873c1f8a6d/cb6abc584a1bfab107ac003d64948a4aef1730aa/b88a511308779c225005d7994b8744561bdbafbc/b8278ff605187ef3fa0f2705e93251cce4c4f8ee/9b1a02e0d980ac6b0e36a90378f847062f81d7e4

Timelineinfo

08/09/2026 CVE reserved
08/15/2026 +6 days Advisory disclosed
08/15/2026 +0 days VulDB entry created
08/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-72126 (🔒)
GCVE (CVE): GCVE-0-2026-72126
GCVE (VulDB): GCVE-100-390545

Entryinfo

Created: 08/15/2026 12:39
Changes: 08/15/2026 12:39 (59)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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