Junglewise Threat Intelligence

CVE-2026-76589: TRENDnet TEW-755AP stack buffer overflow in mycli

CVE-2026-76589 · Severity: critical · CVSS 9.9 · Published 2026-08-19

Technologies: TRENDnet TEW-755AP. Vendors: TRENDnet.

Executive brief

TRENDnet TEW-755AP is a wireless access point used to provide network connectivity. A stack buffer overflow vulnerability in the mycli daemon allows an attacker to trigger a denial of service or potentially execute arbitrary code by sending a specially crafted Wi-Fi SSID configuration, exploitable without direct network access since the SSID is broadcast in beacon frames.

Technical details

A stack-based buffer overflow vulnerability (CWE-121) exists in the /sbin/mycli daemon of TRENDnet TEW-755AP, triggered by improper bounds checking on the SSID argument in function FUN_401000. An attacker can craft a malicious SSID value exceeding the buffer limit (68+ bytes) to overwrite the stack, including the return address. The attack is remotely deliverable via Wi-Fi beacon frame injection and does not require authentication or network access to the device's management interface. Exploitation can result in denial of service or remote code execution; a proof-of-concept has been published publicly.

Affected products

  • TRENDnet TEW-755AP up to 20260702

Timeline

  • 2026-08-19: disclosed
  • other: Public exploit code published on GitHub

References

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