Linux Kernel up to 6.16.3/6.17-rc2 send_ipi_data denial of service

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.16.3/6.17-rc2. This affects the function send_ipi_data. The manipulation leads to denial of service. This vulnerability is uniquely identified as CVE-2025-39704. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.16.3/6.17-rc2 and classified as critical. This issue affects the function send_ipi_data. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Fix stack protector issue in send_ipi_data() Function kvm_io_bus_read() is called in function send_ipi_data(), buffer size of parameter *val should be at least 8 bytes. Since some emulation functions like loongarch_ipi_readl() and kvm_eiointc_read() will write the buffer *val with 8 bytes signed extension regardless parameter len. Otherwise there will be buffer overflow issue when CONFIG_STACKPROTECTOR is enabled. The bug report is shown as follows: Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: send_ipi_data+0x194/0x1a0 [kvm] CPU: 11 UID: 107 PID: 2692 Comm: CPU 0/KVM Not tainted 6.17.0-rc1+ #102 PREEMPT(full) Stack : 9000000005901568 0000000000000000 9000000003af371c 900000013c68c000 900000013c68f850 900000013c68f858 0000000000000000 900000013c68f998 900000013c68f990 900000013c68f990 900000013c68f6c0 fffffffffffdb058 fffffffffffdb0e0 900000013c68f858 911e1d4d39cf0ec2 9000000105657a00 0000000000000001 fffffffffffffffe 0000000000000578 282049464555206e 6f73676e6f6f4c20 0000000000000001 00000000086b4000 0000000000000000 0000000000000000 0000000000000000 9000000005709968 90000000058f9000 900000013c68fa68 900000013c68fab4 90000000029279f0 900000010153f940 900000010001f360 0000000000000000 9000000003af3734 000000004390000c 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1d ... Call Trace: [<9000000003af3734>] show_stack+0x5c/0x180 [<9000000003aed168>] dump_stack_lvl+0x6c/0x9c [<9000000003ad0ab0>] vpanic+0x108/0x2c4 [<9000000003ad0ca8>] panic+0x3c/0x40 [<9000000004eb0a1c>] __stack_chk_fail+0x14/0x18 [<ffff8000023473f8>] send_ipi_data+0x190/0x1a0 [kvm] [<ffff8000023313e4>] __kvm_io_bus_write+0xa4/0xe8 [kvm] [<ffff80000233147c>] kvm_io_bus_write+0x54/0x90 [kvm] [<ffff80000233f9f8>] kvm_emu_iocsr+0x180/0x310 [kvm] [<ffff80000233fe08>] kvm_handle_gspr+0x280/0x478 [kvm] [<ffff8000023443e8>] kvm_handle_exit+0xc0/0x130 [kvm]

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2025-39704 since 04/16/2025. The exploitation is known to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 261607 (Linux Distros Unpatched Vulnerability : CVE-2025-39704), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.16.4 or 6.17-rc3 eliminates this vulnerability. Applying the patch b5b49d341f90eed6de794b6ff34ad3dd66d34343/5c68549c81bcca70fc464e305ffeefd9af968287 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (261607) and CERT Bund (WID-SEC-2025-1988). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• NetApp FAS
• NetApp AFF
• NetApp ActiveIQ Unified Manager
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• Microsoft Azure
• Dell Secure Connect Gateway
• IBM QRadar SIEM
• IBM Security Verify Access
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.17-rc1
• 6.17-rc2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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