# CVE-2026-75013: TOTOLINK EX1200L null pointer dereference in setWizardCfg

Source: https://junglewise.ai/threats/cve-2026-75013-totolink-ex1200l-null-pointer-dereference-in-setwizardcfg  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-17. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-75013 · Severity: medium · CVSS 6.5 · Published 2026-08-17

TOTOLINK EX1200L is a wireless router used in home and small office networks. A vulnerability in its web management interface allows a remote attacker to send a specially crafted request that causes the router's web administration service to crash, resulting in denial of service and temporary loss of management access until the device is rebooted.

Technologies: [TOTOLINK EX1200L](https://junglewise.ai/threats/technologies/ex1200l). Vendors: [TOTOLINK](https://junglewise.ai/threats/vendors/totolink).

## Quick answers

**Is CVE-2026-75013 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-75013 being exploited in the wild.

**How severe is CVE-2026-75013?** Medium severity, with a CVSS score of 6.5, published 17 August 2026.

**Which products and versions are affected?** TOTOLINK EX1200L 9.3.5u.6146_B20201023.

**Is there a fix for CVE-2026-75013?** 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-2026-75013 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-75013?** Check whether you run TOTOLINK EX1200L 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 null pointer dereference vulnerability exists in the setWizardCfg function within the /cgi-bin/cstecgi.cgi CGI binary. The vulnerability occurs when a POST request is sent with incomplete JSON parameters—specifically, providing only the "topicurl" field while omitting required wizard configuration fields. The missing fields propagate as NULL through the parameter handling and string-processing logic, eventually being dereferenced in libc strcoll(), triggering a SIGSEGV crash. The vulnerability is remotely exploitable over the network without authentication. An attacker can reliably crash the cstecgi.cgi process, denying access to the router's web management interface.

## Affected products

- TOTOLINK EX1200L 9.3.5u.6146_B20201023

## Timeline

- 2026-07-01: disclosed: PoC published on GitHub
- 2026-08-17: advisory: CVE-2026-75013 published

## References

- [https://gist.github.com/wyxstarry/21e6c2853891a3beb140a7c879069f9f](https://gist.github.com/wyxstarry/21e6c2853891a3beb140a7c879069f9f)
- [https://vuldb.com/cve/CVE-2026-75013](https://vuldb.com/cve/CVE-2026-75013)

## Related threats

- [TOTOLINK EX1200L null pointer dereference in Password Configuration Handler](https://junglewise.ai/threats/cve-2026-75012-totolink-ex1200l-null-pointer-dereference-in-password)
- [Totolink EX1200L buffer overflow in cstecgi.cgi login](https://junglewise.ai/threats/cve-2026-44089-totolink-ex1200l-buffer-overflow-in-cstecgi-cgi-login)