CVE-2026-22625: HIKSEMI NAS Information Disclosure Flaw

CVE-2026-22625 Overview

CVE-2026-22625 affects certain HIKSEMI Network Attached Storage (NAS) products. The flaw stems from improper handling of filenames, which can expose sensitive system files to an attacker with physical access. The weakness is classified as a path traversal issue [CWE-22].

The vulnerability requires a physical attack vector and no authentication or user interaction. Successful exploitation discloses confidential file contents without affecting integrity or availability. HIKSEMI published a security advisory acknowledging the issue.

Critical Impact
An attacker with physical access to an affected HIKSEMI NAS device can manipulate filename handling to read sensitive system files outside intended directories.

Affected Products

Certain HIKSEMI NAS products (see vendor advisory for specific models)
HIKSEMI firmware versions identified in the Hiksemi Security Advisory
Devices with vulnerable filename parsing logic in storage management components

Discovery Timeline

2026-01-30 - CVE-2026-22625 published to NVD
2026-04-15 - Last updated in NVD database

Technical Details for CVE-2026-22625

Vulnerability Analysis

The vulnerability is a path traversal weakness [CWE-22] in the filename handling logic of affected HIKSEMI NAS products. The device fails to properly sanitize or canonicalize filename inputs before resolving them against the filesystem. As a result, specially crafted filenames containing traversal sequences can escape the intended directory boundary.

An attacker with physical access can supply filenames that reference parent directories or absolute paths. The NAS firmware then resolves these paths and returns contents from locations the user should not access. Targets include configuration files, credential stores, and other system artifacts stored on the device.

The attack requires physical access, which limits remote exploitation. However, NAS devices are often deployed in shared offices, branch sites, or unattended locations. An attacker with brief physical proximity can extract sensitive system data without triggering authentication controls.

Root Cause

The root cause is missing validation of user-supplied filenames before filesystem operations. The affected firmware does not reject ../ sequences or absolute paths during file resolution. This allows traversal beyond the directory intended for user-accessible storage.

Attack Vector

Exploitation requires local physical interaction with the NAS device, such as connecting via a directly attached interface or removable media. The attacker submits a filename containing directory traversal sequences. The firmware processes the request and returns contents of files outside the intended scope, exposing system configuration or credential material.

No verified public exploit code is available. Refer to the Hiksemi Security Advisory for technical specifics.

Detection Methods for CVE-2026-22625

Indicators of Compromise

Unexpected file access events on the NAS referencing paths outside standard user shares
Log entries showing filenames containing ../, ..\, or absolute path prefixes
Physical access events to the NAS device outside maintenance windows

Detection Strategies

Review NAS audit logs for filename strings containing directory traversal sequences
Correlate physical access records (door badge, camera) with NAS file access timestamps
Inspect firmware logs for read operations targeting /etc/, configuration directories, or credential files

Monitoring Recommendations

Forward NAS device logs to a centralized logging or SIEM platform for retention and correlation
Alert on any successful read of system configuration files from non-administrative sessions
Monitor for repeated failed or anomalous filename parsing errors that may indicate probing

How to Mitigate CVE-2026-22625

Immediate Actions Required

Restrict physical access to HIKSEMI NAS devices using locked racks or secured server rooms
Apply the firmware update referenced in the Hiksemi Security Advisory once available for your model
Audit existing NAS logs for prior signs of filename-based traversal attempts
Rotate credentials and keys stored on affected NAS devices after patching

Patch Information

HIKSEMI has published guidance through its security advisory portal. Administrators should consult the Hiksemi Security Advisory to identify affected models and apply the corresponding firmware update. Verify firmware integrity after installation using vendor-provided checksums.

Workarounds

Disable or physically disconnect unused local interfaces on the NAS device
Place affected NAS units in physically controlled environments until firmware is updated
Limit the storage of sensitive credentials or configuration material on affected devices
Enable available device-level encryption to reduce the value of exposed file contents

bash

# Configuration example
# Review vendor advisory for model-specific firmware update procedures
# See: https://www.hiksemitech.com/en/hiksemi/support/security-advisory.html