CVE-2026-53195: 
Linux Kernel vulnerability analysis and mitigation

CVE-2026-53195 is a heap buffer overflow vulnerability in the Linux kernel's USB serial io_ti driver, specifically within the build_i2c_fw_hdr() function. The function allocates a fixed-size buffer of (16*1024 - 512) + sizeof(struct ti_i2c_firmware_rec) bytes but copies up to 65535 bytes from the firmware image's Length field without validating that it fits within the available space. The vulnerability affects the Linux kernel from version 2.6.12 through multiple stable branches, and was disclosed on June 25, 2026. The CVSS score is estimated as Medium; an EPSS score of approximately 0.20% has been assigned (GitHub Advisory, Red Hat Bugzilla).

The root cause is classified as CWE-120 (Buffer Copy without Checking Size of Input — 'Classic Buffer Overflow'). In build_i2c_fw_hdr(), the img_header->Length field is a __le16 value sourced from the firmware file and can range up to 65535. While check_fw_sanity() validates the total firmware image size, it does not specifically validate img_header->Length against the available destination buffer space, allowing a heap overflow when a crafted firmware image is loaded. The fix rejects firmware images where img_header->Length exceeds the available destination space in the allocated buffer (GitHub Advisory).

A local user with the ability to supply a malicious firmware file to the io_ti USB serial driver can trigger a heap buffer overflow during firmware parsing. This could potentially allow arbitrary code execution with kernel privileges, leading to full system compromise, privilege escalation, and loss of confidentiality, integrity, and availability of the affected system (GitHub Advisory, Red Hat Bugzilla).

Patches have been released for multiple stable Linux kernel branches: 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13, and 7.1. Users should update to the patched kernel version for their respective branch. As a workaround until patching is possible, restrict firmware loading to trusted sources only and disable or blacklist the io_ti USB serial driver (modprobe -r io_ti) if it is not required (GitHub Advisory, Red Hat Bugzilla).

Red Hat has acknowledged the vulnerability and tracked it via their Bugzilla system. The Yocto Project security mailing list also referenced the issue. No notable researcher commentary or significant media coverage has been identified beyond standard vulnerability tracking (Red Hat Bugzilla).