# CVE-2026-11504: Tenda CX12L buffer overflow in setSchedWifi

Source: https://junglewise.ai/threats/cve-2026-11504-tenda-cx12l-buffer-overflow-in-setschedwifi  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-08. Updated: 2026-06-08  
License: CC BY 4.0 with a link back

CVE-2026-11504 · Severity: high · CVSS 8.8 · Published 2026-06-08

A security vulnerability exists in the Tenda CX12L router's Wi-Fi scheduling feature. An attacker can exploit this flaw to crash the router's management interface or potentially take control of the device. This could lead to a complete loss of internet connectivity for the network or unauthorized access to the router's settings.

Technologies: [Tenda Cx12l Firmware](https://junglewise.ai/threats/technologies/cx12l-firmware). Vendors: [Tenda](https://junglewise.ai/threats/vendors/tenda).

## Quick answers

**Is CVE-2026-11504 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-11504 being exploited in the wild.

**How severe is CVE-2026-11504?** High severity, with a CVSS score of 8.8, published 8 June 2026.

**Which products and versions are affected?** Tenda Cx12l Firmware 16.03.53.12.

**Is there a fix for CVE-2026-11504?** 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-2026-11504 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2026-11504?** Check whether you run Tenda Cx12l Firmware 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 exists in the 'setSchedWifi' function within the '/goform/openSchedWifi' endpoint of Tenda CX12L firmware version 16.03.53.12. The vulnerability is caused by the use of the unsafe 'strcpy' function to copy user-supplied 'schedStartTime' and 'schedEndTime' parameters into a fixed-size 25-byte heap-allocated buffer without length validation. A remote attacker with low privileges can provide oversized strings to trigger the overflow, leading to memory corruption, a crash of the 'httpd' process (DoS), or potential arbitrary code execution. A public exploit (PoC) has been released.

## Affected products

- Tenda CX12L Router Firmware 16.03.53.12

## Timeline

- 2026-05-22: disclosed: Vulnerability details and PoC shared on GitHub.
- 2026-06-08: advisory: CVE-2026-11504 published in NVD.

## References

- [https://github.com/cve-a/moist/issues/2](https://github.com/cve-a/moist/issues/2)
- [https://vuldb.com/cve/CVE-2026-11504](https://vuldb.com/cve/CVE-2026-11504)
- [https://vuldb.com/submit/835649](https://vuldb.com/submit/835649)
- [https://vuldb.com/vuln/369124](https://vuldb.com/vuln/369124)
- [https://vuldb.com/vuln/369124/cti](https://vuldb.com/vuln/369124/cti)
- [https://www.tenda.com.cn/](https://www.tenda.com.cn/)

## Related threats

- [Tenda CX12L stack overflow in formSetPPTPServer](https://junglewise.ai/threats/cve-2026-8138-tenda-cx12l-stack-overflow-in-formsetpptpserver)
- [Tenda CX12L stack overflow in /goform/NatStaticSetting](https://junglewise.ai/threats/cve-2026-5687-tenda-cx12l-stack-overflow-in-goform-natstaticsetting)
- [Tenda CX12L stack buffer overflow in /goform/RouteStatic](https://junglewise.ai/threats/cve-2026-5686-tenda-cx12l-stack-buffer-overflow-in-goform-routestatic)
- [Tenda CX12L stack buffer overflow in fromAddressNat](https://junglewise.ai/threats/cve-2026-5685-tenda-cx12l-stack-buffer-overflow-in-fromaddressnat)
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