Linux Kernel up to 7.2.12 firewire fw_core_handle_response use after free

Summaryinfo

A vulnerability labeled as very critical has been found in Linux Kernel up to 7.2.12. This issue affects the function fw_core_handle_response of the component firewire. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2026-99185. The attack requires local access. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.2.12. It has been declared as very critical. This vulnerability affects the function fw_core_handle_response of the component firewire. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: firewire: core: fix race condition in split transaction handling For a split transaction, either fw_core_handle_response() or split_transaction_timeout_callback() may manipulate the same transaction entry in the pending transaction list. The return value of timer_delete() is used to determine which function handles the entry. If the transaction is a split transaction and timer_delete() returns zero, the timeout callback may already be running. In this case, the response handler must leave the entry in the list for the timeout callback to remove. A previous code refactoring broke this behavior, introducing a race condition in which both functions could process the same transaction. This could lead to a use-after-free on the transaction initiator side. Fix the regression by ensuring that the response handler does not process the transaction when timer_delete() returns zero. The timeout callback is responsible for removing the entry from the pending transaction list.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-99185 since 09/25/2026. The exploitation appears to be easy. The attack needs to be approached locally. 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 10/28/2026).

Upgrading to version 7.2.13 eliminates this vulnerability. Applying the patch a8caee0e623ca5d56e829032f9ec073c09e4d224/7f9f2d6abc40f79e802b4063859eda343043b85c is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 7.2.0
• 7.2.1
• 7.2.2
• 7.2.3
• 7.2.4
• 7.2.5
• 7.2.6
• 7.2.7
• 7.2.8
• 7.2.9
• 7.2.10
• 7.2.11
• 7.2.12

License

• open-source

Website

• Vendor: https://www.kernel.org/

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