Overview
A stack buffer overflow vulnerability, identified as CVE-2025-59365, has been discovered in specific ASUS router models. This flaw allows an authenticated attacker to potentially compromise the device’s availability by sending a specially crafted request. This vulnerability highlights the importance of keeping your router firmware up-to-date.
Technical Details
CVE-2025-59365 is a stack buffer overflow. This means that a specific input field within the router’s web interface (or another exposed service) can be manipulated with overly long data. When processed, this data overwrites memory beyond the allocated buffer space on the stack. Because this is a stack overflow, it can overwrite return addresses, potentially giving the attacker code execution control. Successful exploitation requires prior authentication, suggesting that the attack surface is limited to those with existing credentials on the device. The specific vulnerable endpoint and input parameter are detailed in the ASUS Security Advisory.
CVSS Analysis
Currently, the Common Vulnerability Scoring System (CVSS) score and severity level for CVE-2025-59365 are marked as N/A (Not Available). This may be because the vulnerability is newly disclosed and further analysis is still underway. Once ASUS publishes more detailed information, the CVSS score will likely be updated.
Possible Impact
The primary impact of exploiting CVE-2025-59365 is a denial-of-service (DoS) condition, rendering the router unavailable. This could disrupt network connectivity for all devices connected to the affected router. While the current assessment indicates only an impact on availability, the potential for remote code execution (RCE) cannot be entirely ruled out until further analysis is completed. Successful remote code execution would have far more severe implications, allowing an attacker to potentially take full control of the device, including intercepting network traffic, changing router settings, and using the router as a launchpad for further attacks on the local network.
Mitigation or Patch Steps
The recommended mitigation is to immediately update your ASUS router’s firmware to the latest version. Refer to the ‘Security Update for ASUS Router Firmware’ section on the ASUS Security Advisory for a list of affected models and the corresponding fixed firmware versions. To update your firmware, follow these general steps:
- Log in to your ASUS router’s web interface. The default address is usually
192.168.1.1or192.168.0.1. You’ll need your router’s administrator username and password. - Navigate to the “Administration” or “Firmware Upgrade” section. The exact location may vary depending on your router model.
- Check for updates. The router should automatically check for and download the latest firmware.
- Follow the on-screen instructions to install the update. Important: Do not interrupt the update process, as this could damage your router.
- After the update is complete, the router will likely reboot. Verify that the new firmware version is installed.
If a firmware update is not yet available for your specific router model, monitor the ASUS Security Advisory page for updates. As a temporary workaround, consider disabling remote management access to your router if it is not strictly necessary. Changing the administrator password to a strong, unique password is also recommended.
References
- ASUS Security Advisory: https://www.asus.com/security-advisory/
