CVE-2023-54242

Kernel crash via zero-weight BFQ division

Published Dec 30, 2025 · Updated Dec 30, 2025

Division by zero in the BFQ block I/O scheduler in Linux allows local users with root privileges to crash the kernel through I/O priorities. bfqq_request_over_limit calculates a request limit by dividing by the hierarchical weight sum without first rejecting a zero divisor. BFQ must be active, and the published reproducer requires root access; successful triggering produces a kernel oops and service interruption.

CVSS severity5.5
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Division by zero in the BFQ block I/O scheduler in Linux allows local users with root privileges to crash the kernel through I/O priorities. bfqq_request_over_limit calculates a request limit by dividing by the hierarchical weight sum without first rejecting a zero divisor. BFQ must be active, and the published reproducer requires root access; successful triggering produces a kernel oops and service interruption.

The record

CVE
CVE-2023-54242
Published
Dec 30, 2025
Updated
Dec 30, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-369, T1499
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Dec 30, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 30, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1655cfc85250a224b0d9486c8136baeea33b9b5c
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c0346a59d719461248c6dc6f21c9e55ef836b66f
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <e53413f8deedf738a6782cc14cc00bd5852ccf18

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1655cfc85250a224b0d9486c8136baeea33b9b5c; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c0346a59d719461248c6dc6f21c9e55ef836b66f; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <e53413f8deedf738a6782cc14cc00bd5852ccf18

Published CVSS scores

5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-369Divide By Zero
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo