What is CVE-2025-6599?

CVE-2025-6599 is a medium-severity vulnerability in Zyxel Dx3301-t0 Firmware, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2025-11-18.

How severe is CVE-2025-6599?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in Zyxel Dx3301-t0 Firmware

CVE-2025-6599

An uncontrolled resource consumption vulnerability in the web server of Zyxel DX3301-T0 firmware version 5.50(ABVY.6.3)C0 and earlier could allow an attacker to perform Slowloris‑style denial‑of‑service (DoS) attacks. Such attacks may temp…

Vulnerability class: DoS (Denial of Service)

EPSS: 0.001 (19.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Zyxel Dx3301-t0 Firmware — versions <= 5.50(ABVY.6.3)C0

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for… (vendor-advisory)

Frequently asked questions

What is CVE-2025-6599?: CVE-2025-6599 is a medium-severity vulnerability in Zyxel Dx3301-t0 Firmware, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2025-11-18.
How severe is CVE-2025-6599?: Medium severity. CVSS v3 base score is 5.3 out of 10.