The Linux kernel vulnerability CVE-2026-23092 involves an out-of-bounds write in the iio: dac: ad3552r-hs driver. The root cause is the misuse of the 'count' parameter as an index for null termination after a call to simple_write_to_buffer(), which returns the actual number of bytes copied. If 'count' exceeds the buffer size (64 bytes), the code writes beyond the stack buffer boundary, leading to a stack buffer overflow. The issue was confirmed via static analysis and testing with a demo module under QEMU. The vulnerability affects multiple specific Linux kernel versions prior to 6.17.0-1021.21~24.04.1. The vendor has released patches correcting this flaw, and users are advised to update accordingly.

This vulnerability allows an out-of-bounds write on the stack, which can lead to memory corruption. The CVSS score of 7.8 reflects high impact on confidentiality, integrity, and availability. An attacker with local access and low privileges could exploit this flaw to compromise the system, potentially leading to arbitrary code execution or system instability.

A patch is available and should be applied. The vendor advisory from Ubuntu confirms that updating to Linux kernel versions 6.17.0-1021.21~24.04.1 or later resolves this issue. After applying the update, a system reboot is required. Due to an ABI change, recompilation and reinstallation of third-party kernel modules may be necessary. Users should follow the vendor's update instructions to ensure full remediation.