CVE-2025-27535 Overview
CVE-2025-27535 is a firmware vulnerability affecting certain Intel Ethernet Connection E825-C network adapters. The vulnerability stems from an exposed ioctl (input/output control) interface with insufficient access control mechanisms in the firmware. This improper access control vulnerability (CWE-782) allows a privileged local attacker to potentially cause a denial of service condition on affected systems.
Critical Impact
A privileged local attacker can exploit the exposed ioctl interface to cause denial of service on systems running vulnerable Intel Ethernet Connection E825-C firmware prior to NVM version 3.84.
Affected Products
- Intel Ethernet Connection E825-C with firmware NVM versions prior to 3.84
- Systems running bare metal operating systems (Ring 0) with vulnerable Intel E825-C network adapters
Discovery Timeline
- 2026-02-10 - CVE CVE-2025-27535 published to NVD
- 2026-02-10 - Last updated in NVD database
Technical Details for CVE-2025-27535
Vulnerability Analysis
This vulnerability exists within the firmware of Intel Ethernet Connection E825-C network adapters. The core issue involves an ioctl interface that is exposed without adequate access control verification. While the vulnerability requires local access and high privileges to exploit, combined with high attack complexity and specific attack requirements, successful exploitation can result in complete loss of availability for the affected system.
The vulnerability operates at Ring 0 (bare metal OS level), meaning it affects the most privileged execution environment. Despite requiring elevated privileges and complex attack conditions, the potential for denial of service makes this a notable security concern for environments utilizing affected Intel network hardware.
Root Cause
The root cause of CVE-2025-27535 is classified under CWE-782: Exposed IOCTL with Insufficient Access Control. The firmware implementation fails to properly validate or restrict access to certain ioctl operations, allowing processes with sufficient privileges to invoke firmware functions that can disrupt normal network adapter operation. This architectural oversight in the access control layer permits abuse of the exposed interface under specific conditions.
Attack Vector
The attack vector for this vulnerability is local, requiring the attacker to have privileged user access to the target system. The exploitation path involves:
- Attaining privileged access (high privilege requirement) to the target system
- Identifying and interacting with the exposed ioctl interface on the Intel E825-C firmware
- Crafting specific ioctl calls that exploit the insufficient access controls
- Triggering a denial of service condition affecting network adapter availability
The attack requires high complexity and specific attack prerequisites to be present, without requiring any user interaction. Exploitation does not result in confidentiality or integrity impacts but causes high availability impact to the vulnerable component.
Detection Methods for CVE-2025-27535
Indicators of Compromise
- Unexpected network adapter failures or restarts on systems with Intel Ethernet Connection E825-C
- Unusual ioctl system calls targeting network device drivers from privileged processes
- Anomalous firmware-level errors or crashes in system logs related to Intel E825-C adapters
Detection Strategies
- Monitor system logs for repeated network adapter failures or unexpected firmware errors on Intel E825-C devices
- Implement endpoint detection and response (EDR) solutions to track privileged process interactions with network device drivers
- Audit privileged user activity on systems containing vulnerable Intel Ethernet hardware
- Deploy firmware integrity monitoring to detect unauthorized firmware access patterns
Monitoring Recommendations
- Enable verbose logging for network adapter events and driver interactions
- Configure alerts for repeated denial of service patterns affecting network connectivity
- Monitor for lateral movement attempts following network disruption events
- Implement baseline monitoring for normal ioctl patterns to detect anomalous activity
How to Mitigate CVE-2025-27535
Immediate Actions Required
- Identify all systems in your environment using Intel Ethernet Connection E825-C adapters
- Verify the current NVM firmware version on all affected devices
- Prioritize firmware updates for systems in critical network infrastructure roles
- Restrict privileged access to systems containing vulnerable hardware
Patch Information
Intel has addressed this vulnerability in NVM version 3.84 and later for the Intel Ethernet Connection E825-C. Organizations should obtain the latest firmware updates through official Intel channels. Detailed patching guidance is available in the Intel Security Advisory INTEL-SA-01171.
Workarounds
- Implement strict privilege access management to limit the number of users with elevated system privileges
- Isolate systems with vulnerable Intel E825-C adapters from untrusted network segments
- Apply defense-in-depth strategies to protect systems where immediate firmware updates are not feasible
- Monitor and restrict local access to affected systems until firmware updates can be applied
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
