Linux Kernel up to 6.15.10/6.16.1 io_uring allocation of resources

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.15.10/6.16.1. This issue affects the function io_uring. The manipulation leads to allocation of resources. This vulnerability is traded as CVE-2025-39793. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.15.10/6.16.1 and classified as critical. This issue affects the function io_uring. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: io_uring/memmap: cast nr_pages to size_t before shifting If the allocated size exceeds UINT_MAX, then it's necessary to cast the mr->nr_pages value to size_t to prevent it from overflowing. In practice this isn't much of a concern as the required memory size will have been validated upfront, and accounted to the user. And > 4GB sizes will be necessary to make the lack of a cast a problem, which greatly exceeds normal user locked_vm settings that are generally in the kb to mb range. However, if root is used, then accounting isn't done, and then it's possible to hit this issue.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2025-39793 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 265245 (Linux Distros Unpatched Vulnerability : CVE-2025-39793), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.15.11, 6.16.2 or 6.17-rc1 eliminates this vulnerability. Applying a patch 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 (265245) and CERT Bund (WID-SEC-2025-2051). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Open Source Linux Kernel

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.5

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

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
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: 265245
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39793

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.15.11/6.16.2/6.17-rc1
Patch: git.kernel.org

Timelineinfo

04/16/2025 CVE reserved
09/12/2025 +149 days Advisory disclosed
09/12/2025 +0 days VulDB entry created
11/27/2025 +76 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39793 (🔒)
GCVE (CVE): GCVE-0-2025-39793
GCVE (VulDB): GCVE-100-323789
CERT Bund: WID-SEC-2025-2051 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 09/12/2025 23:16
Updated: 11/27/2025 03:38
Changes: 09/12/2025 23:16 (57), 09/15/2025 15:45 (7), 09/18/2025 22:16 (2), 11/27/2025 03:38 (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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