---
id: "CVE-2026-99087"
kind: "vulnerability"
aliases: ["CVE-2026-99087"]
title: "Linux kernel dm-integrity: NULL pointer crash when activated in read-only mode"
severity: "unknown"
cvss: null
epss: 0.00206
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["device-mapper", "dm-integrity", "linux-kernel", "runtime"]
not_affected_if: ["no-dm-integrity"]
published_at: "2026-10-23T13:17:33+00:00"
first_seen_at: "2026-10-23T21:57:34+00:00"
updated_at: "2026-10-25T12:38:50+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99087", "first_seen_at": "2026-10-23T21:57:34+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-99087", "first_seen_at": "2026-10-25T12:38:50+00:00"}]
---

# Linux kernel dm-integrity: NULL pointer crash when activated in read-only mode

When a dm-integrity device has its dirty bitmap flag set and is activated in 'R' mode, the kernel dereferences a NULL pointer while reading the journal during resume. The result is a kernel crash, which is a denial of service on the host.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- unknown

## Fix

- unknown

## Timeline

- 2026-10-23T21:57:34+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-99087
- 2026-10-25T12:38:50+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-99087

## From the sources

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

dm-integrity: fix NULL pointer dereference when the 'R' flag is used

If the dm-integrity device has the SB_FLAG_DIRTY_BITMAP flag set and the
user activates the device in the 'R' mode, a crash in dm_integrity_resume
happens because the function attempts to read the journal containing the
bitmap.

This patch makes dm-integrity skip any writes to the device in
dm_integrity_resume if the device is activated in the 'R' mode.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_