Linux Kernel up to 6.16-rc1 net_sched race condition

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in Linux Kernel up to 6.16-rc1. The affected element is an unknown function of the component net_sched. Performing a manipulation results in race condition. This vulnerability is known as CVE-2025-38193. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.16-rc1. It has been classified as problematic. This affects some unknown functionality of the component net_sched. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net_sched: sch_sfq: reject invalid perturb period Gerrard Tai reported that SFQ perturb_period has no range check yet, and this can be used to trigger a race condition fixed in a separate patch. We want to make sure ctl->perturb_period * HZ will not overflow and is positive. tc qd add dev lo root sfq perturb -10 # negative value : error Error: sch_sfq: invalid perturb period. tc qd add dev lo root sfq perturb 1000000000 # too big : error Error: sch_sfq: invalid perturb period. tc qd add dev lo root sfq perturb 2000000 # acceptable value tc -s -d qd sh dev lo qdisc sfq 8005: root refcnt 2 limit 127p quantum 64Kb depth 127 flows 128 divisor 1024 perturb 2000000sec Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-38193 since 04/16/2025. The exploitability is told to be difficult. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 243500 (Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2025-1111)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.186, 6.1.142, 6.6.95, 6.12.35, 6.15.4 or 6.16-rc2 eliminates this vulnerability. Applying the patch 956b5aebb349449b38d920d444ca1392d43719d1/b11a50544af691b787384089b68f740ae20a441b/0357da9149eac621f39e235a135ebf155f01f7c3/f9b97d466e6026ccbdda30bb5b71965b67ccbc82/590b2d7d0beadba2aa576708a05a05f0aae39295/7ca52541c05c832d32b112274f81a985101f9ba8 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 (243500), EUVD (EUVD-2025-20063) and CERT Bund (WID-SEC-2025-1465). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

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

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.9

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 243500
Nessus Name: Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2025-1111)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.186/6.1.142/6.6.95/6.12.35/6.15.4/6.16-rc2
Patch: 956b5aebb349449b38d920d444ca1392d43719d1/b11a50544af691b787384089b68f740ae20a441b/0357da9149eac621f39e235a135ebf155f01f7c3/f9b97d466e6026ccbdda30bb5b71965b67ccbc82/590b2d7d0beadba2aa576708a05a05f0aae39295/7ca52541c05c832d32b112274f81a985101f9ba8

Timelineinfo

04/16/2025 CVE reserved
07/04/2025 +79 days Advisory disclosed
07/04/2025 +0 days VulDB entry created
12/19/2025 +168 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38193 (🔒)
GCVE (CVE): GCVE-0-2025-38193
GCVE (VulDB): GCVE-100-314925
EUVD: 🔒
CERT Bund: WID-SEC-2025-1465 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 07/04/2025 16:23
Updated: 12/19/2025 05:40
Changes: 07/04/2025 16:23 (57), 07/04/2025 21:07 (1), 07/20/2025 17:48 (7), 08/05/2025 12:15 (2), 08/25/2025 16:15 (1), 08/29/2025 00:12 (1), 09/02/2025 12:50 (1), 09/11/2025 01:44 (1), 09/21/2025 01:32 (1), 11/02/2025 23:48 (1), 12/08/2025 05:43 (1), 12/19/2025 05:40 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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