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Response snapshot Oct 27, 2026, 00:46 UTC

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VulnerabilityCVE-2026-98941

Linux kernel: ext4: don't enable large folios on encrypted inodes

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.

At a glance

Exploited
Not known
Severity
7.0 High (CVSS 3.1)
Chance of exploitation
0.1% in the next 30 days
Sources
1 source

What to do

Check the vendor advisory for affected versions and fixes.

Read NVD CVE-2026-98941 (opens a new tab)

What happened

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

Continue reading

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.

Scores and how they were measured

CVSS base severity

7.0

Version 3.1As of

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

0.1%

Scored Percentile 3.4%

Model and measurement source (opens a new tab)

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Related technology

Sources

  1. Primary source

    NVD CVE-2026-98941 (opens a new tab)

    NVD record: description, CVSS (the CNA score is preferred), affected products, and publication date. Not evidence of exploitation.

    Published Checked

  2. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  3. Primary source

    FIRST measured EPSS score (opens a new tab)

    Measured EPSS probability and percentile for CVE-2026-98941, scored 2026-10-26. This is a model estimate, not proof of exposure.

    Published Checked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, October 24). Linux kernel: ext4: don't enable large folios on encrypted inodes (CVE-2026-98941). https://kevwire.com/record/CVE-2026-98941

MLA

"Linux kernel: ext4: don't enable large folios on encrypted inodes (CVE-2026-98941)." KEVWire, 24 Oct. 2026, kevwire.com/record/CVE-2026-98941.

Chicago

KEVWire. "Linux kernel: ext4: don't enable large folios on encrypted inodes (CVE-2026-98941)." Last modified October 24, 2026. https://kevwire.com/record/CVE-2026-98941.

Evidence summary (plain text)

Linux kernel: ext4: don't enable large folios on encrypted inodes (Oct 23, 2026).
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.
CVSS 7.0 (version 3.1; evidence as of Oct 24, 2026; https://nvd.nist.gov/vuln/detail/CVE-2026-98941).
EPSS 0.1% for the following 30 days, scored Oct 26, 2026 (https://api.first.org/data/v1/epss?cve=CVE-2026-98941&date=2026-10-26).
Sources:
NVD CVE-2026-98941: https://nvd.nist.gov/vuln/detail/CVE-2026-98941
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?pubStartDate=2026-10-12T13:35:55.142Z&pubEndDate=2026-10-26T13:35:55.142Z&resultsPerPage=500&startIndex=9000
FIRST measured EPSS score: https://api.first.org/data/v1/epss?cve=CVE-2026-98941&date=2026-10-26
Record ID: CVE-2026-98941.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Oct 26, 2026, 19:40 UTC. Ingestion is not an independent editorial investigation.

NVD status: Received. Publication in the NVD is not evidence of exploitation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

Record JSON

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Record details

Record detail