CVE-2026-23253

CVE Details

Release Date:	2026-03-18
Impact:	Moderate	What is this?

Description

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.

See more information about CVE-2026-23253 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	6.2
Vector String:	CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	High
Privileges Required:	None
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	Low
Integrity Impact:	Low
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 10 (kernel-uek)	ELSA-2026-50372	2026-07-02
Oracle Linux version 9 (kernel-uek)	ELSA-2026-50372	2026-07-02