Linux Kernel up to 6.1.137/6.6.89/6.12.27/6.14.5 sch_hfsc hfsc_qlen_notify cleanup

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5.4	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.137/6.6.89/6.12.27/6.14.5. It has been rated as problematic. Affected by this issue is the function hfsc_qlen_notify of the component sch_hfsc. The manipulation leads to an unknown weakness. This vulnerability is traded as CVE-2025-38177. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.137/6.6.89/6.12.27/6.14.5. It has been rated as problematic. This issue affects the function hfsc_qlen_notify of the component sch_hfsc. Using CWE to declare the problem leads to CWE-459. The product does not properly "clean up" and remove temporary or supporting resources after they have been used. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: sch_hfsc: make hfsc_qlen_notify() idempotent hfsc_qlen_notify() is not idempotent either and not friendly to its callers, like fq_codel_dequeue(). Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers' life: 1. update_vf() decreases cl->cl_nactive, so we can check whether it is non-zero before calling it. 2. eltree_remove() always removes RB node cl->el_node, but we can use RB_EMPTY_NODE() + RB_CLEAR_NODE() to make it safe.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2025-38177 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 242345 (Ubuntu 20.04 LTS : Linux kernel (Intel IoTG) vulnerabilities (USN-7655-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.138, 6.6.90, 6.12.28 or 6.14.6 eliminates this vulnerability. Applying the patch 0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87/9030a91235ae4845ec71902c3e0cecfc9ed1f2df/d06476714d2819b550e0cc39222347e2c8941c9d/c1175c4ad01dbc9c979d099861fa90a754f72059/51eb3b65544c9efd6a1026889ee5fb5aa62da3bb 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 (242345), EUVD (EUVD-2025-20019) 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

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.137
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.6.58
• 6.6.59
• 6.6.60
• 6.6.61
• 6.6.62
• 6.6.63
• 6.6.64
• 6.6.65
• 6.6.66
• 6.6.67
• 6.6.68
• 6.6.69
• 6.6.70
• 6.6.71
• 6.6.72
• 6.6.73
• 6.6.74
• 6.6.75
• 6.6.76
• 6.6.77
• 6.6.78
• 6.6.79
• 6.6.80
• 6.6.81
• 6.6.82
• 6.6.83
• 6.6.84
• 6.6.85
• 6.6.86
• 6.6.87
• 6.6.88
• 6.6.89
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.14.0
• 6.14.1
• 6.14.2
• 6.14.3
• 6.14.4
• 6.14.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
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CPE 2.2info

• 🔒
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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cleanup
CWE: CWE-459
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: 242345
Nessus Name: Ubuntu 20.04 LTS : Linux kernel (Intel IoTG) vulnerabilities (USN-7655-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.138/6.6.90/6.12.28/6.14.6
Patch: 0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87/9030a91235ae4845ec71902c3e0cecfc9ed1f2df/d06476714d2819b550e0cc39222347e2c8941c9d/c1175c4ad01dbc9c979d099861fa90a754f72059/51eb3b65544c9efd6a1026889ee5fb5aa62da3bb

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-2025-38177 (🔒)
GCVE (CVE): GCVE-0-2025-38177
GCVE (VulDB): GCVE-100-314909
EUVD: 🔒
CERT Bund: WID-SEC-2025-1465 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 07/04/2025 16:18
Updated: 12/19/2025 03:25
Changes: 07/04/2025 16:18 (57), 07/04/2025 16:46 (1), 07/19/2025 15:26 (2), 07/20/2025 16:13 (7), 08/25/2025 14:20 (1), 08/29/2025 00:12 (1), 09/02/2025 11:13 (1), 09/10/2025 16:16 (1), 09/19/2025 08:47 (1), 11/02/2025 23:42 (1), 12/08/2025 02:05 (1), 12/19/2025 03:25 (11)
Complete: 🔍
Cache ID: 216::103

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Discussion

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