Linux Kernel up to 6.16.4/6.17-rc3 HID i2c_subip_regs array index

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.16.4/6.17-rc3. Affected by this issue is the function i2c_subip_regs of the component HID. Performing a manipulation results in array index. This vulnerability is known as CVE-2025-39818. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.16.4/6.17-rc3. This affects the function i2c_subip_regs of the component HID. The manipulation with an unknown input leads to a array index vulnerability. CWE is classifying the issue as CWE-129. The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: HID: intel-thc-hid: intel-thc: Fix incorrect pointer arithmetic in I2C regs save Improper use of secondary pointer (&dev->i2c_subip_regs) caused kernel crash and out-of-bounds error: BUG: KASAN: slab-out-of-bounds in _regmap_bulk_read+0x449/0x510 Write of size 4 at addr ffff888136005dc0 by task kworker/u33:5/5107 CPU: 3 UID: 0 PID: 5107 Comm: kworker/u33:5 Not tainted 6.16.0+ #3 PREEMPT(voluntary) Workqueue: async async_run_entry_fn Call Trace: <TASK> dump_stack_lvl+0x76/0xa0 print_report+0xd1/0x660 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? kasan_complete_mode_report_info+0x26/0x200 kasan_report+0xe1/0x120 ? _regmap_bulk_read+0x449/0x510 ? _regmap_bulk_read+0x449/0x510 __asan_report_store4_noabort+0x17/0x30 _regmap_bulk_read+0x449/0x510 ? __pfx__regmap_bulk_read+0x10/0x10 regmap_bulk_read+0x270/0x3d0 pio_complete+0x1ee/0x2c0 [intel_thc] ? __pfx_pio_complete+0x10/0x10 [intel_thc] ? __pfx_pio_wait+0x10/0x10 [intel_thc] ? regmap_update_bits_base+0x13b/0x1f0 thc_i2c_subip_pio_read+0x117/0x270 [intel_thc] thc_i2c_subip_regs_save+0xc2/0x140 [intel_thc] ? __pfx_thc_i2c_subip_regs_save+0x10/0x10 [intel_thc] [...] The buggy address belongs to the object at ffff888136005d00 which belongs to the cache kmalloc-rnd-12-192 of size 192 The buggy address is located 0 bytes to the right of allocated 192-byte region [ffff888136005d00, ffff888136005dc0) Replaced with direct array indexing (&dev->i2c_subip_regs[i]) to ensure safe memory access.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-39818 since 04/16/2025. The exploitability is told to be difficult. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/27/2025).

The vulnerability scanner Nessus provides a plugin with the ID 265153 (Linux Distros Unpatched Vulnerability : CVE-2025-39818), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.16.5 or 6.17-rc4 eliminates this vulnerability. Applying the patch 78d4cf0466c79452e47aa6f720afbde63e709ccc/a7fc15ed629be89e51e09b743277c53e0a0168f5 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 (265153) and CERT Bund (WID-SEC-2025-2077). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM QRadar SIEM
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.16.4
• 6.17-rc1
• 6.17-rc2
• 6.17-rc3

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

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