Quick answers
- Is CVE-2026-9389 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-9389 being exploited in the wild.
- How severe is CVE-2026-9389?
- High severity, with a CVSS score of 8.8, published 24 May 2026.
- Which products and versions are affected?
- Tenda F456 1.0.0.5.
- Is there a fix for CVE-2026-9389?
- 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-2026-9389 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-9389?
- Check whether you run Tenda F456 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 exists in the 'httpd' service of Tenda F456 firmware version 1.0.0.5. The flaw is located within the 'frmL7ImForm' function in the '/goform/L7Im' component. The vulnerability is caused by the unsafe use of 'sprintf' when processing the 'page' parameter, which lacks proper length validation before being copied into a fixed-size stack buffer. A remote attacker with low privileges can exploit this by sending a specially crafted POST request, potentially leading to remote code execution (RCE) or a denial of service (DoS). Public exploit code (PoC) has been disclosed.
Affected products
- Tenda F456 1.0.0.5
Timeline
- 2026-05-24: disclosed: Public disclosure of the vulnerability and PoC.
- 2026-05-24: advisory