CVE-2026-23253
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-665
- Record status
- Modified
Affected
- Linux Kernel < 5.10.253
- Linux Kernel < 5.15.203
- Linux Kernel < 6.1.167
- Linux Kernel < 6.6.130
- Linux Kernel < 6.12.77
- Linux Kernel < 6.18.17
- Linux Kernel < 6.19.7
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-23253.md and follow it. Check whether this project is affected by CVE-2026-23253. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/32eb8e4adc207ef31bc6e5ae56bab940b0176066
- https://git.kernel.org/stable/c/527cfa8a3486b3555c5c15e2f62be484a11398dc
- https://git.kernel.org/stable/c/af050ab44fa1b1897a940d7d756e512232f5e5df
- https://git.kernel.org/stable/c/bfbc0b5b32a8f28ce284add619bf226716a59bc0
- https://git.kernel.org/stable/c/cfd94642025e6f71c8f754bdec0800ee95e4f3dd
- https://git.kernel.org/stable/c/d71781bad59b1c9d60d7068004581f9bf19c0c9d
- https://git.kernel.org/stable/c/f1e520ca2e83ece6731af6167c9e5e16931ecba0
- https://git.kernel.org/stable/c/fb378cf89be434ed1f10ab79cc4788fba8ae868d
References
- https://git.kernel.org/stable/c/32eb8e4adc207ef31bc6e5ae56bab940b0176066
- https://git.kernel.org/stable/c/527cfa8a3486b3555c5c15e2f62be484a11398dc
- https://git.kernel.org/stable/c/af050ab44fa1b1897a940d7d756e512232f5e5df
- https://git.kernel.org/stable/c/bfbc0b5b32a8f28ce284add619bf226716a59bc0
- https://git.kernel.org/stable/c/cfd94642025e6f71c8f754bdec0800ee95e4f3dd
- https://git.kernel.org/stable/c/d71781bad59b1c9d60d7068004581f9bf19c0c9d
- https://git.kernel.org/stable/c/f1e520ca2e83ece6731af6167c9e5e16931ecba0
- https://git.kernel.org/stable/c/fb378cf89be434ed1f10ab79cc4788fba8ae868d
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html