VDB-312907 · CVE-2025-38071 · EUVD-2025-18582

Linux Kernel up to 6.1.140/6.6.92/6.12.30/6.14.8 memblock_phys_alloc_range return value

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.
4.9	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.140/6.6.92/6.12.30/6.14.8. It has been rated as problematic. Affected by this issue is the function memblock_phys_alloc_range. This manipulation causes return value. This vulnerability is tracked as CVE-2025-38071. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.1.140/6.6.92/6.12.30/6.14.8 and classified as problematic. Affected by this vulnerability is the function memblock_phys_alloc_range. The manipulation with an unknown input leads to a return value vulnerability. The CWE definition for the vulnerability is CWE-252. The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: x86/mm: Check return value from memblock_phys_alloc_range() At least with CONFIG_PHYSICAL_START=0x100000, if there is < 4 MiB of contiguous free memory available at this point, the kernel will crash and burn because memblock_phys_alloc_range() returns 0 on failure, which leads memblock_phys_free() to throw the first 4 MiB of physical memory to the wolves. At a minimum it should fail gracefully with a meaningful diagnostic, but in fact everything seems to work fine without the weird reserve allocation.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-38071 since 04/16/2025. The exploitation appears to be difficult. 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 02/19/2026).

The vulnerability scanner Nessus provides a plugin with the ID 241773 (Amazon Linux 2023 : bpftool, kernel6.12, kernel6.12-modules-extra (ALAS2023-2025-1052)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.141, 6.6.93, 6.12.31 or 6.14.9 eliminates this vulnerability. Applying the patch 8c18c904d301ffeb33b071eadc55cd6131e1e9be/bffd5f2815c5234d609725cd0dc2f4bc5de2fc67/c6f2694c580c27dca0cf7546ee9b4bfa6b940e38/dde4800d2b0f68b945fd81d4fc2d4a10ae25f743/631ca8909fd5c62b9fda9edda93924311a78a9c4 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 (241773), EUVD (EUVD-2025-18582) and CERT Bund (WID-SEC-2025-1350). 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
SUSE openSUSE
Open Source Linux Kernel
RESF Rocky Linux
Dell Avamar
Dell NetWorker
Dell Secure Connect Gateway
IBM QRadar SIEM

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: 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

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Return value
CWE: CWE-252 / CWE-253
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍