Live › vulnerability › CVE-2026-98941
Go to dashboardEnabling the encrypt feature on a mounted ext4 filesystem bypasses a mount-time check, so writing encrypted data can trigger a kernel NULL pointer dereference and crash. The fix disables large folios on encrypted inodes, as already done for data-journaling inodes.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.
Systems running Linux kernels from v6.19 through v7.2 that write encrypted data to ext4 filesystems where the encrypt feature was enabled on an already-mounted filesystem. Kernels v7.3 and later are not affected, and systems that never enable the encrypt feature after mount are less exposed since mount-time checks still apply.
No product ranges from the sources yet.
uname -r to see whether the running kernel is between v6.19 and v7.2tune2fs -l /dev/sdX | grep features to check whether the encrypt feature is enabled on a mounted ext4 filesystemEach row is the first time that source carried this signal. The analyst’s rows are its own findings.
In the Linux kernel, the following vulnerability has been resolved:
ext4: don't enable large folios on encrypted inodes
Commit 709f0f1f1bf5 ("ext4: add checks for large folio incompatibilities when BS > PS") disables large folios at mount time if the "encrypt" feature is set. However, enabling that feature on a mounted filesystem circumvents that check, and writing encrypted data results in a crash:
BUG: kernel NULL pointer dereference, address: 0000000000000028 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work RIP: 0010:ext4_finish_bio+0xf7/0x3e0 Call Trace: ext4_release_io_end+0x51/0x110 ext4_end_io_end+0x4c/0xe0 ext4_end_io_rsv_work+0xb3/0x100
Fix this by disabling large folios on encrypted inodes, as is already done for inodes that use data journaling.
This affects all kernels between v6.19 and v7.2, but it is not needed in v7.3, where the code was significantly refactored.
This page as .md · .json · in your agent: get_signal("CVE-2026-98941")
NVD data is provided by NIST and is public domain · EPSS scores by FIRST, used with attribution. Posts quoted belong to their authors.