A stack-based buffer overflow vulnerability exists in the tmUnblock.cgi endpoint of the Linksys WRT120N wireless router. The vulnerability is triggered by sending a specially crafted HTTP POST request with an overly long TM_Block_URL parameter to the endpoint. By exploiting this flaw, an unauthenticated remote attacker can overwrite memory in a controlled manner, enabling them to temporarily reset the administrator password of the device to a blank value. This grants unauthorized access to the router’s web management interface without requiring valid credentials.
Published: 2025-07-31
Updated: 2025-07-31
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 5.3
Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00111