Linux Kernel CVE-2026-46329

EROFS (Enhanced Read-Only File System) is a compressed, high-performance read-only filesystem used in Android, embedded Linux, and OCI container image layers. When EROFS is configured in file-backed mode - where the filesystem image resides in a regular file rather than a raw block device, analogous to a loopback mount - the kernel block layer must synthesize zeroed responses for I/O requests that fall beyond the end of the underlying image file. The vulnerability was introduced at commit ce63cb62d794c98c7631c2296fa845f2a8d0a4a1 and affects the EROFS block I/O path, which failed to implement this boundary clamping. The affected CPE is cpe:2.3:a:linux:linux:* across multiple stable series. No CWE is formally assigned; the root cause is most consistent with CWE-125 (Out-of-bounds Read) or improper boundary condition handling in block I/O completion paths. The intelligence tags include 'Information Disclosure,' which conflicts with the CVSS C:N metric - this discrepancy suggests a possible secondary confidentiality impact (e.g., exposure of kernel buffer contents beyond the image boundary) that is not reflected in the current NVD scoring.