---
title: "CVE-2026-89499: Linux Kernel - Race Condition"
description: "Linux kernel contains a race condition in ring-buffer remote reader update caused by improper handling of swap_reader_page callback failure, letting remote readers cause inconsistent page state, exploit requires event storm on small buffer."
url: https://panop.io/threat-heartbeat/CVE-2026-89499/
---

# CVE-2026-89499 Linux Kernel - Race Condition

Linux kernel contains a race condition in ring-buffer remote reader update caused by improper handling of swap\_reader\_page callback failure, letting remote readers cause inconsistent page state, exploit requires event storm on small buffer.

CVSS base score 7.8 /10

High

CISA KEV

Not listed

Public exploit

None known

Authentication

Required

EPSS

0.17% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-89499)

## Details

Type

Race Condition

Impact

Denial Of Service

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Published

11 September 2026

Updated

15 October 2026

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-89499](https://nvd.nist.gov/vuln/detail/CVE-2026-89499)
- [https://git.kernel.org/stable/c/5eab74874d11160725c42ab676ba97a797a362eb](https://git.kernel.org/stable/c/5eab74874d11160725c42ab676ba97a797a362eb)
- [https://git.kernel.org/stable/c/a14a97048e48471e283d76879b83d2ae323e0722](https://git.kernel.org/stable/c/a14a97048e48471e283d76879b83d2ae323e0722)

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- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
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