Linux Kernel up to 6.18.2 fuse copy_finish uring reference count

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.18.2. This affects the function copy_finish of the component fuse. Executing a manipulation of the argument uring can lead to reference count. This vulnerability is tracked as CVE-2025-68791. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.18.2 and classified as critical. This vulnerability affects the function copy_finish of the component fuse. The manipulation of the argument uring with an unknown input leads to a reference count vulnerability. The CWE definition for the vulnerability is CWE-911. The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: fuse: missing copy_finish in fuse-over-io-uring argument copies Fix a possible reference count leak of payload pages during fuse argument copies. [Joanne: simplified error cleanup]

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2025-68791 since 12/24/2025. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 307005 (Ubuntu 25.10 : Linux kernel vulnerabilities (USN-8177-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.18.3 or 6.19-rc1 eliminates this vulnerability. Applying the patch b79938863f436960eff209130f025c4bd3026bf8/6e0d7f7f4a43ac8868e98c87ecf48805aa8c24dd 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 (307005) and CERT Bund (WID-SEC-2026-0086). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Reference count
CWE: CWE-911 / CWE-664
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 307005
Nessus Name: Ubuntu 25.10 : Linux kernel vulnerabilities (USN-8177-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.3/6.19-rc1
Patch: b79938863f436960eff209130f025c4bd3026bf8/6e0d7f7f4a43ac8868e98c87ecf48805aa8c24dd

Timelineinfo

12/24/2025 CVE reserved
01/13/2026 +20 days Advisory disclosed
01/13/2026 +0 days VulDB entry created
04/19/2026 +96 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-68791 (🔒)
GCVE (CVE): GCVE-0-2025-68791
GCVE (VulDB): GCVE-100-340672
CERT Bund: WID-SEC-2026-0086 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 01/13/2026 17:47
Updated: 04/19/2026 21:36
Changes: 01/13/2026 17:47 (60), 03/27/2026 08:01 (7), 04/19/2026 21:36 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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