VDB-309698 · CVE-2025-37915 · EUVD-2025-15931

Linux Kernel up to 6.15-rc4 net_sched use after free

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7.3	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.15-rc4 and classified as critical. This issue affects some unknown processing of the component net_sched. Such manipulation leads to use after free. This vulnerability is listed as CVE-2025-37915. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.15-rc4. It has been rated as critical. Affected by this issue is an unknown code of the component net_sched. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net_sched: drr: Fix double list add in class with netem as child qdisc As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of drr, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before adding to the list to cover for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2025-37915 since 04/16/2025. The exploitation is known to be easy. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 12/14/2025).

The vulnerability scanner Nessus provides a plugin with the ID 237223 (Debian dsa-5925 : affs-modules-6.1.0-33-4kc-malta-di - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.182, 6.1.138, 6.6.90, 6.12.28, 6.14.6 or 6.15-rc5 eliminates this vulnerability. Applying the patch 2968632880f1792007eedd12eeedf7f6e2b7e9f3/4f0ecf50cdf76da95828578a92f130b653ac2fcf/db205b92dfe0501e5b92fb7cf00971d0e44ba3eb/26e75716b94d6ff9be5ea07d63675c4d189f30b4/ab2248110738d4429668140ad22f530a9ee730e1/f99a3fbf023e20b626be4b0f042463d598050c9a 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 (237223), EUVD (EUVD-2025-15931) and CERT Bund (WID-SEC-2025-1114). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

Debian Linux
Amazon Linux 2
Red Hat Enterprise Linux
Ubuntu Linux
SUSE Linux
Oracle Linux
SUSE openSUSE
Dell Avamar
Open Source Linux Kernel
Dell NetWorker
Dell Secure Connect Gateway

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

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

NVD Base Score: 7.0
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: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍