CVE-2026-23995: EVerest Buffer Overflow Vulnerability

CVE-2026-23995 Overview

CVE-2026-23995 is a stack-based buffer overflow vulnerability in EVerest, an open-source electric vehicle (EV) charging software stack. The vulnerability exists in the CAN interface initialization routines, where passing an interface name longer than IFNAMSIZ (16 bytes) to CAN open routines causes an overflow of ifreq.ifr_name, corrupting adjacent stack data and potentially enabling arbitrary code execution. A malicious or misconfigured interface name can trigger this vulnerability before any privilege checks are performed.

Critical Impact

Local attackers can exploit this stack-based buffer overflow to achieve code execution on EV charging infrastructure by providing an oversized interface name during CAN interface initialization.

Affected Products

• EVerest EV Charging Software Stack versions prior to 2026.02.0

Discovery Timeline

• 2026-03-26 - CVE CVE-2026-23995 published to NVD
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-23995

Vulnerability Analysis

This vulnerability is classified as CWE-121 (Stack-based Buffer Overflow). The root cause lies in the CAN interface initialization code where input validation is insufficient. When the software processes an interface name for CAN bus communication, it copies the provided name into the ifreq.ifr_name buffer without properly checking the length against the IFNAMSIZ limit of 16 bytes.

The attack requires local access to the system, but does not require any authentication or user interaction to exploit. Successful exploitation can lead to complete compromise of confidentiality, integrity, and availability of the affected EV charging system.

Root Cause

The vulnerability stems from improper input validation when handling interface names in the CAN interface initialization routines. The ifreq.ifr_name buffer has a fixed size defined by IFNAMSIZ (16 bytes), but the code fails to validate that the provided interface name fits within this constraint before copying. This missing boundary check allows an attacker-controlled string to overflow the stack buffer, overwriting adjacent stack memory including return addresses and saved registers.

Attack Vector

The attack vector is local, requiring the attacker to have access to the system running EVerest. The exploitation flow involves:

1. An attacker provides a maliciously crafted interface name exceeding 16 characters to the CAN initialization routines
2. The oversized name overflows the ifreq.ifr_name stack buffer
3. Adjacent stack data is corrupted, potentially including return addresses
4. Carefully crafted overflow data can redirect execution flow to attacker-controlled code

The vulnerability is particularly concerning because it occurs before privilege checks are performed, meaning that the overflow can be triggered early in the initialization process. For technical details on the vulnerability mechanics, refer to the GitHub Security Advisory.

Detection Methods for CVE-2026-23995

Indicators of Compromise

• Unexpected crashes or segmentation faults in EVerest CAN interface initialization logs
• Anomalous interface names in system logs exceeding 16 characters
• Unexpected process behavior or child processes spawned from EVerest components
• Core dump files indicating stack corruption in CAN-related functions

Detection Strategies

• Monitor system logs for interface initialization failures with unusually long interface name strings
• Implement file integrity monitoring on EVerest binaries to detect post-exploitation modifications
• Deploy runtime application self-protection (RASP) solutions to detect stack smashing attempts
• Configure audit rules to track interface configuration changes on EV charging infrastructure

Monitoring Recommendations

• Enable stack canary and ASLR verification in system security configurations
• Monitor for unusual CAN bus interface registration attempts with abnormal naming patterns
• Implement centralized logging for all EV charging infrastructure to correlate potential exploitation attempts
• Set up alerts for EVerest process crashes that may indicate exploitation attempts

How to Mitigate CVE-2026-23995

Immediate Actions Required

• Upgrade EVerest to version 2026.02.0 or later immediately
• Audit all interface naming configurations to ensure none exceed 15 characters
• Restrict local access to systems running EVerest to authorized personnel only
• Enable compiler-level protections such as stack canaries and ASLR if not already active

Patch Information

The EVerest project has released version 2026.02.0 which contains a patch for this vulnerability. Organizations running affected versions should prioritize upgrading to the patched version. The security advisory and patch details are available in the GitHub Security Advisory.

Workarounds

• Implement strict input validation at the application layer to reject interface names exceeding IFNAMSIZ (16 bytes)
• Apply network segmentation to isolate EV charging infrastructure from untrusted networks
• Use mandatory access control (MAC) systems like SELinux or AppArmor to limit the impact of potential exploitation
• Monitor and restrict local user access to EVerest configuration interfaces

# Example: Verify EVerest version and check for vulnerable installations
# Check installed version
everest --version

# If version is below 2026.02.0, upgrade immediately
# Follow vendor documentation for proper upgrade procedures