CVE-2026-98067

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

erofs: disable LZ4 rolling decompression for now

LZ4 rolling decompression [1] was introduced to reduce the memory

footprint of temporary pages:

For many cases, it is needed for users to read small data within

a compressed extent (pcluster), either due to random small read, or

since uptodate folios (typically order-0) cannot be reused for

decompression again since decompression algorithm refills

already-uptodate folios.

Rolling decompression works because LZ4 is LZ77-based and only refers

to the most recent 64 KiB of decompressed data, so in theory only a

bounded rolling window of temporary pages is needed when decompressing.

It can save a lot of temporary memory, e.g.

601,960-byte data can be compressed into a 256k LZ4 compressed extent,

which means it needs 146 extra pages per request in the worst case if

rolling decompression is disabled.

However, the upstream LZ4 implementation is not under EROFS' con

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References