---
id: "CVE-2026-98724"
kind: "vulnerability"
aliases: ["CVE-2026-98724"]
title: "Linux kernel NVMe target: short SGL segment reads memory out of bounds"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["kernel", "linux", "nvme", "pci-epf", "runtime"]
not_affected_if: ["default-config"]
published_at: "2026-10-18T16:17:26+00:00"
first_seen_at: "2026-10-23T21:57:16+00:00"
updated_at: "2026-10-25T05:17:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98724", "first_seen_at": "2026-10-23T21:57:16+00:00"}]
---

# Linux kernel NVMe target: short SGL segment reads memory out of bounds

The Linux kernel's NVMe PCI endpoint target driver (nvmet pci-epf) does not reject SGL segments whose length is smaller than one descriptor. A host can send such a segment to trigger an out-of-bounds read of kernel memory and a negative descriptor count.

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

## How to check

- unknown

## Fix

- unknown

## Timeline

- 2026-10-23T21:57:16+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98724

## From the sources

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

nvmet: pci-epf: reject too-short SGL segments

The host controls an SGL segment's length. A nonzero length smaller than
one SGL descriptor makes nr_descs zero, so
nvmet_pci_epf_get_sgl_segment() reads the type byte of sgls[-1] outside
the allocated buffer. If that byte contains a segment descriptor type,
the function also copies the preceding 16 bytes and returns a negative
descriptor count.

The read was reproduced in 3/3 KASAN boots with only the host transfer
mocked by a KUnit test:

  BUG: KASAN: slab-out-of-bounds in nvmet_pci_epf_get_sgl_segment
  Read of size 1 by task kunit_try_catch
  Call Trace:
   nvmet_pci_epf_get_sgl_segment
   nvmet_pci_epf_short_sgl_test
  Kernel panic - not syncing: KASAN: panic_on_warn set ...

Reject segments that cannot hold one descriptor before allocating or
transferring their contents.

---

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