Linux Kernel up to 6.3.1 sched fq_change credit integer overflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.6	$0-$5k	0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 5.10.179/5.15.110/6.1.27/6.2.14/6.3.1 and classified as critical. Affected is the function fq_change of the component sched. The manipulation of the argument credit leads to integer overflow. This vulnerability is documented as CVE-2023-53624. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.10.179/5.15.110/6.1.27/6.2.14/6.3.1. It has been rated as critical. This issue affects the function fq_change of the component sched. The manipulation of the argument credit with an unknown input leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_fq: fix integer overflow of "credit" if sch_fq is configured with "initial quantum" having values greater than INT_MAX, the first assignment of "credit" does signed integer overflow to a very negative value. In this situation, the syzkaller script provided by Cristoph triggers the CPU soft-lockup warning even with few sockets. It's not an infinite loop, but "credit" wasn't probably meant to be minus 2Gb for each new flow. Capping "initial quantum" to INT_MAX proved to fix the issue. v2: validation of "initial quantum" is done in fq_policy, instead of open coding in fq_change() _ suggested by Jakub Kicinski

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2023-53624 since 10/07/2025. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/20/2026).

The vulnerability scanner Nessus provides a plugin with the ID 276910 (SUSE SLES12 Security Update : kernel (SUSE-SU-2025:4189-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.180, 5.15.111, 6.1.28, 6.2.15 or 6.3.2 eliminates this vulnerability. Applying the patch 4b8a05e3801661a0438fcd0cdef181030d966a5a/d0b43125ec892aeb1b03e5df5aab595097da225a/4fbefeab88c6e79753a25099d455d3d59d2946b4/85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad/2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd/7041101ff6c3073fd8f2e99920f535b111c929cb is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (276910) and CERT Bund (WID-SEC-2025-2229). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• Open Source Linux Kernel
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.179
• 5.15.110
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8
• 6.2.9
• 6.2.10
• 6.2.11
• 6.2.12
• 6.2.13
• 6.2.14
• 6.3.0
• 6.3.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 276910
Nessus Name: SUSE SLES12 Security Update : kernel (SUSE-SU-2025:4189-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.180/5.15.111/6.1.28/6.2.15/6.3.2
Patch: 4b8a05e3801661a0438fcd0cdef181030d966a5a/d0b43125ec892aeb1b03e5df5aab595097da225a/4fbefeab88c6e79753a25099d455d3d59d2946b4/85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad/2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd/7041101ff6c3073fd8f2e99920f535b111c929cb

Timelineinfo

10/07/2025 Advisory disclosed
10/07/2025 +0 days CVE reserved
10/07/2025 +0 days VulDB entry created
04/20/2026 +195 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53624 (🔒)
GCVE (CVE): GCVE-0-2023-53624
GCVE (VulDB): GCVE-100-327491
CERT Bund: WID-SEC-2025-2229 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/07/2025 19:26
Updated: 04/20/2026 03:09
Changes: 10/07/2025 19:26 (60), 11/23/2025 00:18 (7), 11/27/2025 21:43 (2), 12/22/2025 08:14 (1), 02/05/2026 19:47 (11), 03/01/2026 09:31 (1), 04/20/2026 03:09 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

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