The Linux kernel contained a vulnerability in the arm_ffa firmware component where the PARTITION_INFO_GET_REGS operation trusted firmware-supplied indices when copying partition descriptors into a caller buffer. This lack of validation allowed inconsistent counts or index progressions to cause the copy loop to write beyond the allocated array bounds, leading to potential memory corruption. The issue was fixed by rejecting inconsistent counts and correcting the index handling when exactly one descriptor is present in the first fragment. This vulnerability affects numerous Linux kernel versions prior to 7.0.0-1010.10 and related versions, with patches released in Ubuntu kernel packages. The CVSS 3.1 score is 8.4 (AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating a high-impact local vulnerability without privileges or user interaction required.

Successful exploitation could allow a local attacker to cause memory corruption by writing past allocated array bounds in the ARM firmware framework, potentially leading to privilege escalation or system compromise. The CVSS score of 8.4 reflects high confidentiality, integrity, and availability impacts. However, exploitation requires local access and no user interaction is needed. No known exploits in the wild have been reported at this time.

A patch is available and should be applied promptly. Users should update their Linux kernel packages to the fixed versions as listed in the Ubuntu advisories (e.g., linux-image-7.0.0-1009-aws 7.0.0-1009.9 and others). After updating, a system reboot is required to apply the changes. Due to an ABI change, recompilation and reinstallation of all third-party kernel modules are necessary. Follow vendor instructions carefully to ensure full remediation.