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

Source: https://junglewise.ai/threats/cve-2026-76589-trendnet-tew-755ap-stack-buffer-overflow-in-mycli  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-19. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

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

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.

Technologies: [TRENDnet TEW-755AP](https://junglewise.ai/threats/technologies/tew-755ap). Vendors: [TRENDnet](https://junglewise.ai/threats/vendors/trendnet).

## Quick answers

**Is CVE-2026-76589 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-76589 being exploited in the wild.

**How severe is CVE-2026-76589?** Critical severity, with a CVSS score of 9.9, published 19 August 2026.

**Which products and versions are affected?** TRENDnet TEW-755AP up to 20260702.

**Is there a fix for CVE-2026-76589?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-76589 attacked?** It is attacked over the network or from the adjacent network, in a network appliance.

**Am I affected by CVE-2026-76589?** Check whether you run TRENDnet TEW-755AP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## 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

- [https://github.com/meishigana/CVE/blob/main/team15_20260702/13_755ap-mycli-bof/poc/poc-mycli-overflow.py](https://github.com/meishigana/CVE/blob/main/team15_20260702/13_755ap-mycli-bof/poc/poc-mycli-overflow.py)
- [https://github.com/meishigana/CVE/tree/main/team15_20260702/13_755ap-mycli-bof](https://github.com/meishigana/CVE/tree/main/team15_20260702/13_755ap-mycli-bof)

## Related threats

- [TRENDnet TEW-755AP command injection in SSI email function](https://junglewise.ai/threats/cve-2026-76591-trendnet-tew-755ap-command-injection-in-ssi-email-function)
- [TRENDnet TEW-755AP stack buffer overflow in WAN configuration](https://junglewise.ai/threats/cve-2026-76590-trendnet-tew-755ap-stack-buffer-overflow-in-wan-configuration)