---
id: CVE-2026-23253
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  media: dvb-core: fix wrong reinitialization of ringbuffer on reopen

  dvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the
  DVR device
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  media: dvb-core: fix wrong reinitialization of ringbuffer on reopen

  dvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the
  DVR device.  dvb_ringbuffer_…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.17, < 5.10.253'
  - 'linux_kernel >= 5.11, < 5.15.203'
  - 'linux_kernel >= 5.16, < 6.1.167'
  - 'linux_kernel >= 6.2, < 6.6.130'
  - 'linux_kernel >= 6.7, < 6.12.77'
  - 'linux_kernel >= 6.13, < 6.18.17'
  - 'linux_kernel >= 6.19, < 6.19.7'
  - linux_kernel = 7.0
patched:
  - linux_kernel 6.19.7
published: '2026-03-18'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:18:44.787'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23253'
references:
  - url: 'https://git.kernel.org/stable/c/32eb8e4adc207ef31bc6e5ae56bab940b0176066'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/527cfa8a3486b3555c5c15e2f62be484a11398dc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/af050ab44fa1b1897a940d7d756e512232f5e5df'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/bfbc0b5b32a8f28ce284add619bf226716a59bc0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cfd94642025e6f71c8f754bdec0800ee95e4f3dd'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d71781bad59b1c9d60d7068004581f9bf19c0c9d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f1e520ca2e83ece6731af6167c9e5e16931ecba0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/fb378cf89be434ed1f10ab79cc4788fba8ae868d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00129
epssPercentile: 0.02261
ingestedAt: '2026-10-15T03:30:12.837Z'
---

## Overview

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

media: dvb-core: fix wrong reinitialization of ringbuffer on reopen

dvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the
DVR device.  dvb_ringbuffer_init() calls init_waitqueue_head(), which
reinitializes the waitqueue list head to empty.

Since dmxdev->dvr_buffer.queue is a shared waitqueue (all opens of the
same DVR device share it), this orphans any existing waitqueue entries
from io_uring poll or epoll, leaving them with stale prev/next pointers
while the list head is reset to {self, self}.

The waitqueue and spinlock in dvr_buffer are already properly
initialized once in dvb_dmxdev_init().  The open path only needs to
reset the buffer data pointer, size, and read/write positions.

Replace the dvb_ringbuffer_init() call in dvb_dvr_open() with direct
assignment of data/size and a call to dvb_ringbuffer_reset(), which
properly resets pread, pwrite, and error with correct memory ordering
without touching the waitqueue or spinlock.

## Affected

- `linux_kernel >= 2.6.17, < 5.10.253`
- `linux_kernel >= 5.11, < 5.15.203`
- `linux_kernel >= 5.16, < 6.1.167`
- `linux_kernel >= 6.2, < 6.6.130`
- `linux_kernel >= 6.7, < 6.12.77`
- `linux_kernel >= 6.13, < 6.18.17`
- `linux_kernel >= 6.19, < 6.19.7`
- `linux_kernel = 7.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.19.7`