CVE-2026-71936
HighCVSS 7.2Exploitation Probability (EPSS)
Low risk39th percentile - higher than 39% of all known CVEs
Summary
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the sysreboot function. The issue is caused by unsafe concatenation of split valueN data into a fixed-size buffer. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
Risk Assessment
The risk includes disruption of device operation or takeover, potentially leading to network integrity compromise and service unavailability.
Recommendation
Immediately update the firmware of DrayTek VigorSwitch devices to the latest patched version and restrict management interface access to trusted administrators only.
Other vulnerabilities in DrayTek VigorSwitch
See all- CVE-2026-71933Critical
Multiple DrayTek VigorSwitch models contain unauthorized operation vulnerabilities in multiple syslog functions. The vulnerability is caused by missing authorization checks. A remote attacker can trigger these vulnerabilities via crafted requests to modify configuration, restart services, save startup configuration, or clear logs.
- CVE-2026-71921Critical
Multiple DrayTek VigorSwitch models contain a pre-authentication command injection vulnerability in the setget.cgi interface. The vulnerability is caused by insufficient filtering of the pass field before command execution. A remote attacker can trigger this vulnerability via crafted input to execute arbitrary commands with root privileges.
- CVE-2026-71943High
Multiple DrayTek VigorSwitch models contain a command injection vulnerability in the setDevNet function. The vulnerability is caused by insufficient filtering of the username and password fields before command execution. A remote attacker can trigger this vulnerability via crafted input to execute arbitrary commands with root privileges. Exploitation requires valid administrative credentials for the device's web management interface.
- CVE-2026-71942High
Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the mail_mailalert function. The vulnerability is caused by concatenating multiple smtpReceiver email addresses into a fixed-size buffer without checking the remaining buffer size. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface.
- CVE-2026-71941High
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the diag_logmail function. The issue is caused by concatenating multiple smtpReceiver email addresses into a fixed-size buffer without checking remaining space. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
- CVE-2026-71940High
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the acl_general_setup Edit ACE function. The issue is caused by copying the name field into a fixed-size buffer without length validation. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
- CVE-2026-71939High
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the acl_general_setup Add ACE function. The issue is caused by copying the name field into a fixed-size buffer without length validation. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
- CVE-2026-71938High
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the switch_lan_gvrp function. The issue is caused by unsafe copying of the portList field into an undersized buffer. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
- CVE-2026-71937High
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the poe_schedule_profile function. The issue is caused by repeated concatenation of start_date, start_time, duration_time, how_often, weekdays, monthly_date, and cycle_duration fields into small fixed-size buffers without proper length checks. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
- CVE-2026-71935High
Multiple DrayTek VigorSwitch models have a buffer overflow vulnerability in the webBackupAction function. The issue is caused by repeated string concatenation of pathN, valueN, key, and option fields into fixed-size stack buffers without total length checks. A remote attacker can trigger this via crafted input, causing denial of service or potential arbitrary command execution. Valid administrative credentials for the web management interface are required.
Original NVD description (English source)
Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the sysreboot function. The vulnerability is caused by unsafe concatenation of split valueN data into a fixed-size buffer. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface.

