erofs Interlaced Plain Extent Identification Vulnerability

Publication date: 2026-05-06

Last updated on: 2026-05-08

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: erofs: fix interlaced plain identification for encoded extents Only plain data whose start position and on-disk physical length are both aligned to the block size should be classified as interlaced plain extents. Otherwise, it must be treated as shifted plain extents. This issue was found by syzbot using a crafted compressed image containing plain extents with unaligned physical lengths, which can cause OOB read in z_erofs_transform_plain().

CVSS Scores

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Meta Information

Published

2026-05-06

Last Modified

2026-05-08

Generated

2026-07-06

AI Q&A

2026-05-06

EPSS Evaluated

2026-07-05

NVD

CVE-2026-43166

EUVD

EUVD-2026-27729

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*
linux_kernel	erofs	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability exists in the Linux kernel's erofs file system implementation. It involves incorrect classification of certain plain data extents when their start position and physical length on disk are not aligned to the block size. Specifically, plain data with unaligned physical lengths was mistakenly treated as interlaced plain extents instead of shifted plain extents. This misclassification can lead to an out-of-bounds (OOB) read error in the function z_erofs_transform_plain().

Impact Analysis

The vulnerability can cause an out-of-bounds read in the Linux kernel when processing specially crafted compressed images containing unaligned plain extents. This could potentially lead to system instability, crashes, or exposure of unintended memory contents, depending on how the kernel handles the OOB read.

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