# CVE-2026-124060: TOTOLINK CA300-PoE buffer overflow in UploadCustomModule

Source: https://junglewise.ai/threats/cve-2026-124060-a-vulnerability-was-detected-in-totolink-ca300-poe-6-2c-884  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-07. Updated: 2026-11-07  
License: CC BY 4.0 with a link back

CVE-2026-124060 · Severity: critical · CVSS 9.1 · Published 2026-11-07

TOTOLINK CA300-PoE is a network access point device used for enterprise connectivity and network access control. A buffer overflow vulnerability in the UploadCustomModule function allows a remote attacker to upload malicious code and execute arbitrary commands on the device without authentication, potentially compromising the entire network infrastructure it controls.

Technologies: [TOTOLINK CA300-PoE](https://junglewise.ai/threats/technologies/ca300-poe). Vendors: [TOTOLINK](https://junglewise.ai/threats/vendors/totolink).

## Quick answers

**Is CVE-2026-124060 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-124060 being exploited in the wild.

**How severe is CVE-2026-124060?** Critical severity, with a CVSS score of 9.1, published 7 November 2026.

**Which products and versions are affected?** TOTOLINK CA300-PoE 6.2c.884.

**Is there a fix for CVE-2026-124060?** 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-2026-124060 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-124060?** Check whether you run TOTOLINK CA300-PoE 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 buffer overflow vulnerability exists in the UploadCustomModule function of /cgi-bin/cstecgi.cgi in TOTOLINK CA300-PoE, where the File parameter is not properly validated. An attacker can send a crafted HTTP request with an oversized File argument to overflow a buffer and execute arbitrary code remotely without authentication. The vulnerability is confirmed exploitable in the wild.

## Affected products

- TOTOLINK CA300-PoE 6.2c.884

## Timeline

- 2026-11-07: disclosed
- exploited: exploit is public and may be used in wild

## References

- [https://lavender-bicycle-a5a.notion.site/TOTOLINK-CA300-PoE-UploadCustomModule-3f953a41781f803fabf6e4b901fffb1f?source=copy_link](https://lavender-bicycle-a5a.notion.site/TOTOLINK-CA300-PoE-UploadCustomModule-3f953a41781f803fabf6e4b901fffb1f?source=copy_link)
- [https://vuldb.com/cve/CVE-2026-124060](https://vuldb.com/cve/CVE-2026-124060)

## Related threats

- [TOTOLINK CA300-PoE buffer overflow in WiFi configuration](https://junglewise.ai/threats/cve-2026-124059-a-security-vulnerability-has-been-detected-in-totolink-ca300-poe)
- [TOTOLINK CA300-PoE buffer overflow in WiFi repeater configuration](https://junglewise.ai/threats/cve-2026-124058-a-weakness-has-been-identified-in-totolink-ca300-poe-6-2c-884)
- [TOTOLINK CA300-PoE buffer overflow in setWiFiMultipleConfig](https://junglewise.ai/threats/cve-2026-124057-a-security-flaw-has-been-discovered-in-totolink-ca300-poe-6-2c)
- [TOTOLINK CA300-PoE buffer overflow in setWiFiBasicConfig](https://junglewise.ai/threats/cve-2026-123961-a-security-vulnerability-has-been-detected-in-totolink-ca300-poe)
- [TOTOLINK CA300-PoE buffer overflow in setWanConfig](https://junglewise.ai/threats/cve-2026-123960-a-weakness-has-been-identified-in-totolink-ca300-poe-6-2c-884)