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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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 temporarily block legitimate HTTP requests and partially disrupt access to the web management interface, while other networking services remain unaffected.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.34% probability · 27th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Affected
- zyxel/lte3301-plus firmware · zyxel/nr5103 firmware · zyxel/nr5103e firmware · zyxel/nr5309 firmware · zyxel/nr7302 firmware · zyxel/nr7303 firmware · zyxel/nebula fwa505 firmware · zyxel/nebula fwa510 firmware · zyxel/nebula fwa515 firmware · zyxel/nebula fwa710 firmware · zyxel/dm4200-b0 firmware · zyxel/dx3300-t0 firmware · zyxel/dx3300-t1 firmware · zyxel/dx3301-t0 firmware · zyxel/dx4510-b1 firmware · zyxel/dx5401-b0 firmware · zyxel/dx5401-b1 firmware · zyxel/ee3301-00 firmware · zyxel/ee5301-00 firmware · zyxel/ee6510-10 firmware · +40 more
- Source
- security@zyxel.com.tw
EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.