CVE-2026-53149: 
Linux Kernel vulnerability analysis and mitigation

CVE-2026-53149 is an out-of-bounds read vulnerability in the Linux kernel's Thunderbolt subsystem, specifically in the __tb_property_parse_dir() function. The flaw was published on June 25, 2026, and affects Linux kernel versions from 4.15 onward, with fixes available in stable releases 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13, and 7.1. It carries a CVSS v3.1 base score of 5.5 (Medium) (Red Hat CVE, Feedly).

The root cause is a missing bounds check (CWE-125: Out-of-bounds Read) in __tb_property_parse_dir() within the Linux kernel's Thunderbolt subsystem. When the root directory's length field equals or exceeds block_len - 2, the function computes content_offset and content_len without verifying that their sum fits within block_len, causing the entry parsing loop to read past the end of the allocated property block. Exploitation requires a local attacker to supply a malicious Thunderbolt device or otherwise trigger Thunderbolt property parsing with a crafted directory structure. The fix adds a bounds check after computing content_offset and content_len to reject directories whose content extends past the block (Red Hat CVE, Feedly).

Successful exploitation can result in disclosure of kernel memory contents to a local attacker, as the out-of-bounds read may expose data from adjacent memory regions beyond the allocated property block. The vulnerability has no impact on integrity or availability (CVSS scores both as None), and its scope is limited to the local system without privilege escalation or lateral movement potential. The primary risk is information disclosure of sensitive kernel memory (Red Hat CVE, Feedly).

Update the Linux kernel to a patched version: 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13, or 7.1 and later. As a workaround where patching is not immediately possible, restrict physical access to Thunderbolt ports or disable Thunderbolt support in the kernel/BIOS if the feature is not required. Kernel patches are tracked via multiple stable-tree commits in the official Linux kernel repository (Red Hat CVE, Feedly).