# CVE-2026-6015: Tenda AC9 stack-based buffer overflow in QuickIndex

Source: https://junglewise.ai/threats/cve-2026-6015-tenda-ac9-stack-based-buffer-overflow-in-quickindex  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-10. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2026-6015 · Severity: high · CVSS 8.8 · Published 2026-04-10

A security vulnerability has been identified in the Tenda AC9 router, a device used to provide wireless internet in homes and small offices. An attacker could exploit this flaw to disrupt the router's operations or potentially take control of the device. This could lead to a total loss of internet connectivity or unauthorized access to the network traffic passing through the router.

Technologies: [Tenda Ac9](https://junglewise.ai/threats/technologies/ac9), [Tenda Ac9 Firmware](https://junglewise.ai/threats/technologies/ac9-firmware). Vendors: [Tenda](https://junglewise.ai/threats/vendors/tenda).

## Quick answers

**Is CVE-2026-6015 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-6015 being exploited in the wild.

**How severe is CVE-2026-6015?** High severity, with a CVSS score of 8.8, published 10 April 2026.

**Which products and versions are affected?** Tenda AC9 15.03.02.13.

**Is there a fix for CVE-2026-6015?** 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-2026-6015 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-6015?** Check whether you run Tenda Ac9 or Tenda Ac9 Firmware. 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 exists in the Tenda AC9 router firmware version 15.03.02.13. The flaw is located within the 'formQuickIndex' function in the '/goform/QuickIndex' file, which serves as a POST request handler. An attacker can trigger the overflow by providing a specially crafted, overly long string to the 'PPPOEPassword' argument. While the attack requires low-level authentication (PR:L), it can be executed remotely over the network. Successful exploitation could allow for remote code execution (RCE) or a denial of service (DoS) condition. Public exploit code has been disclosed.

## Affected products

- Tenda AC9 15.03.02.13

## Timeline

- 2026-04-10: disclosed: Vulnerability disclosed and CVE assigned
- 2026-04-10: advisory

## References

- [https://lavender-bicycle-a5a.notion.site/Tenda-AC9-QuickIndex-33153a41781f80458940f212f150a4fb?source=copy_link](https://lavender-bicycle-a5a.notion.site/Tenda-AC9-QuickIndex-33153a41781f80458940f212f150a4fb?source=copy_link)
- [https://vuldb.com/submit/791828](https://vuldb.com/submit/791828)
- [https://vuldb.com/vuln/356571](https://vuldb.com/vuln/356571)
- [https://vuldb.com/vuln/356571/cti](https://vuldb.com/vuln/356571/cti)
- [https://www.tenda.com.cn/](https://www.tenda.com.cn/)

## Related threats

- [Tenda AC9 stack buffer overflow in POST request handler](https://junglewise.ai/threats/cve-2026-104611-a-vulnerability-was-detected-in-tenda-ac9-15-03-02-13-affected)
- [Tenda AC9 authentication bypass in web management](https://junglewise.ai/threats/cve-2026-86300-tenda-ac9-authentication-bypass-in-web-management)
- [Tenda AC9 stack overflow in WizardHandle decodePwd](https://junglewise.ai/threats/cve-2026-6016-tenda-ac9-stack-overflow-in-wizardhandle-decodepwd)
- [Tenda AC7, AC9, and AC10 Routers Command Injection Vulnerability](https://junglewise.ai/threats/cve-2018-14558-tenda-ac7-ac9-and-ac10-routers-command-injection-vulnerability)