Linux Kernel up to 6.16.7/6.17-rc5 fuse fuse_dev_do_write out-of-bounds write

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.
7.7$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.16.7/6.17-rc5. Affected is the function fuse_dev_do_write of the component fuse. Such manipulation leads to out-of-bounds write. This vulnerability is referenced as CVE-2025-39888. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.16.7/6.17-rc5. It has been rated as critical. Affected by this issue is the function fuse_dev_do_write of the component fuse. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: fuse: Block access to folio overlimit syz reported a slab-out-of-bounds Write in fuse_dev_do_write. When the number of bytes to be retrieved is truncated to the upper limit by fc->max_pages and there is an offset, the oob is triggered. Add a loop termination condition to prevent overruns.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2025-39888 since 04/16/2025. The exploitation is known to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 02/16/2026).

The vulnerability scanner Nessus provides a plugin with the ID 265878 (Linux Distros Unpatched Vulnerability : CVE-2025-39888), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.16.8 or 6.17-rc6 eliminates this vulnerability. Applying the patch 623719227b114d73a2cee45f1b343ced63ce09ec/9d81ba6d49a7457784f0b6a71046818b86ec7e44 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 (265878) and CERT Bund (WID-SEC-2025-2107). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Google Container-Optimized OS
  • 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 Secure Connect Gateway
  • IBM QRadar SIEM
  • Dell NetWorker

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

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

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 265878
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39888

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.16.8/6.17-rc6
Patch: 623719227b114d73a2cee45f1b343ced63ce09ec/9d81ba6d49a7457784f0b6a71046818b86ec7e44

Timelineinfo

04/16/2025 CVE reserved
09/23/2025 +160 days Advisory disclosed
09/23/2025 +0 days VulDB entry created
02/16/2026 +146 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39888 (🔒)
GCVE (CVE): GCVE-0-2025-39888
GCVE (VulDB): GCVE-100-325610
CERT Bund: WID-SEC-2025-2107 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/23/2025 08:39
Updated: 02/16/2026 10:48
Changes: 09/23/2025 08:39 (59), 09/28/2025 18:35 (2), 12/02/2025 05:07 (7), 12/13/2025 10:30 (11), 01/12/2026 09:56 (1), 02/16/2026 10:48 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Interested in the pricing of exploits?

See the underground prices here!