CVE-2026-89748

High

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. The current !retry test reverses both outcomes. It returns an error after a successful final replacement, leaving the link update complete but the reader bookkeeping unfinished. After a failed final replacement, it falls through and updates the head and reader pointers as though the replacement succeeded, which can corrupt the ring. Treat only a negative counter as exhaustion and return the documented -EBUSY error.

Package Linux Kernel
Published 2026-09-11
Last modified 2026-09-13
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

7.8

out of 10
High
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected versions

Linux kernel versions 7.1 and later are affected. Fixed in 7.2.4, 7.3-rc1 and their respective stable series.

Affected from
≥ 7.1
Fixed in
✓ 7.2.4 7.2.x ✓ 7.3-rc1

Frequently asked questions

  • What is CVE-2026-89748?

    CVE-2026-89748 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 7.1 onward and has been patched in 7.2.4 and 7.3-rc1. CVE-2026-89748 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-89748?

    CVE-2026-89748 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H .

  • Is there a patch available for CVE-2026-89748?

    Yes. CVE-2026-89748 has been patched. Fixed versions include 7.2.4 and 7.3-rc1. If you are running Linux kernel 7.1 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-89748 actively exploited?

    No. CVE-2026-89748 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.