CVE-2025-6599: An uncontrolled resource consumption vulnerability in the web server of Zyxel DX3301-T0 firmware version…

CVE-2025-6599 · Severity: medium · CVSS 5.3 · Published 2025-11-18

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.

Technologies: Zyxel Ax7501-B1 Firmware, Zyxel Dx3300-T0, Zyxel Ex3501-T0, Zyxel Nebula Fwa515, Zyxel VMG4005-B50B. Vendors: Zyxel.

Quick answers

Is CVE-2025-6599 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-6599 being exploited in the wild.
How severe is CVE-2025-6599?
Medium severity, with a CVSS score of 5.3, published 18 November 2025.
Which products and versions are affected?
Zyxel Ax7501-B0, Zyxel Ax7501-B0 Firmware, Zyxel Ax7501-B1, Zyxel Ax7501-B1 Firmware and 128 more. The advisory does not name versions.
Is there a fix for CVE-2025-6599?
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.
Am I affected by CVE-2025-6599?
Check whether you run Zyxel Ax7501-B0, Zyxel Ax7501-B0 Firmware, Zyxel Ax7501-B1 or one of the others listed. 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.

Affected products

  • Zyxel Ax7501-B0
  • Zyxel Ax7501-B0 Firmware
  • Zyxel Ax7501-B1
  • Zyxel Ax7501-B1 Firmware
  • Zyxel Dm4200-B0
  • Zyxel Dm4200-B0 Firmware
  • Zyxel Dx3300-T0
  • Zyxel Dx3300-T0 Firmware
  • Zyxel Dx3300-T1
  • Zyxel Dx3300-T1 Firmware
  • Zyxel Dx3301-T0
  • Zyxel Dx3301-T0 Firmware
  • Zyxel Dx4510-B1
  • Zyxel DX4510-B1 firmware
  • Zyxel Dx5401-B0
  • Zyxel Dx5401-B0 Firmware
  • Zyxel Dx5401-B1
  • Zyxel Dx5401-B1 Firmware
  • Zyxel Ee3301-00
  • Zyxel Ee3301-00 Firmware
  • Zyxel Ee5301-00
  • Zyxel Ee5301-00 Firmware
  • Zyxel Ee6510-10
  • Zyxel Ee6510-10 Firmware
  • Zyxel Emg3525-T50b
  • Zyxel Emg3525-T50b Firmware
  • Zyxel Emg5523-T50b
  • Zyxel Emg5523-T50b Firmware
  • Zyxel Emg5723-T50k
  • Zyxel Emg5723-T50k Firmware
  • Zyxel Emg6726-B10a
  • Zyxel Emg6726-B10a Firmware
  • Zyxel Ex3300-T0
  • Zyxel Ex3300-T0 Firmware
  • Zyxel Ex3300-T1
  • Zyxel Ex3300-T1 Firmware
  • Zyxel Ex3301-T0
  • Zyxel Ex3301-T0 Firmware
  • Zyxel Ex3500-T0
  • Zyxel Ex3500-T0 Firmware
  • Zyxel Ex3501-T0
  • Zyxel Ex3501-T0 Firmware
  • Zyxel Ex3600-T0
  • Zyxel Ex3600-T0 Firmware
  • Zyxel Ex5401-B0
  • Zyxel Ex5401-B0 Firmware
  • Zyxel Ex5401-B1
  • Zyxel Ex5401-B1 Firmware
  • Zyxel Ex5501-B0
  • Zyxel Ex5501-B0 Firmware
  • Zyxel Ex5510-B0
  • Zyxel Ex5510-B0 Firmware
  • Zyxel Ex5512-T0
  • Zyxel Ex5512-T0 Firmware
  • Zyxel Ex5601-T0
  • Zyxel Ex5601-T0 Firmware
  • Zyxel Ex5601-T1
  • Zyxel Ex5601-T1 Firmware
  • Zyxel Ex7501-B0
  • Zyxel Ex7501-B0 Firmware
  • Zyxel Ex7710-B0
  • Zyxel Ex7710-B0 Firmware
  • Zyxel Gm4100-B0
  • Zyxel Gm4100-B0 Firmware
  • Zyxel LTE3301-PLUS
  • Zyxel Lte3301-Plus Firmware
  • Zyxel Nebula Fwa505
  • Zyxel Nebula Fwa505 Firmware
  • Zyxel Nebula Fwa510
  • Zyxel Nebula Fwa510 Firmware
  • Zyxel Nebula Fwa515
  • Zyxel Nebula Fwa515 Firmware
  • Zyxel Nebula Fwa710
  • Zyxel Nebula Fwa710 Firmware
  • Zyxel Nr5103
  • Zyxel Nr5103 Firmware
  • Zyxel Nr5103e
  • Zyxel Nr5103e Firmware
  • Zyxel Nr5309
  • Zyxel Nr5309 Firmware
  • Zyxel Nr7302
  • Zyxel Nr7302 Firmware
  • Zyxel Nr7303
  • Zyxel Nr7303 Firmware
  • Zyxel Pe3301-00
  • Zyxel Pe3301-00 Firmware
  • Zyxel Pe5301-01
  • Zyxel Pe5301-01 Firmware
  • Zyxel Pm3100-T0
  • Zyxel PM3100-T0 firmware
  • Zyxel Pm5100-T0
  • Zyxel PM5100-T0 firmware
  • Zyxel Pm7300-T0
  • Zyxel PM7300-T0 firmware
  • Zyxel Pm7500-00
  • Zyxel PM7500-00 firmware
  • Zyxel Px3321-T1
  • Zyxel Px3321-T1 Firmware
  • Zyxel Px5301-T0
  • Zyxel Px5301-T0 Firmware
  • Zyxel Scr 50axe
  • Zyxel Scr 50axe Firmware
  • Zyxel Vmg3625-T50b
  • Zyxel Vmg3625-T50b Firmware
  • Zyxel Vmg3927-B50b
  • Zyxel Vmg3927-B50b Firmware
  • Zyxel Vmg3927-T50k
  • Zyxel Vmg3927-T50k Firmware
  • Zyxel Vmg4005-B50a
  • Zyxel Vmg4005-B50a Firmware
  • Zyxel VMG4005-B50B
  • Zyxel Vmg4005-B50b Firmware
  • Zyxel Vmg4005-B60a
  • Zyxel Vmg4005-B60a Firmware
  • Zyxel Vmg4927-B50a
  • Zyxel Vmg4927-B50a Firmware
  • Zyxel Vmg8623-T50b
  • Zyxel Vmg8623-T50b Firmware
  • Zyxel Vmg8825-T50k
  • Zyxel Vmg8825-T50k Firmware
  • Zyxel We3300-00
  • Zyxel We3300-00 Firmware
  • Zyxel Wx3100-T0
  • Zyxel Wx3100-T0 Firmware
  • Zyxel Wx3401-B0
  • Zyxel Wx3401-B0 Firmware
  • Zyxel Wx3401-B1
  • Zyxel Wx3401-B1 Firmware
  • Zyxel Wx5600-T0
  • Zyxel Wx5600-T0 Firmware
  • Zyxel Wx5610-B0
  • Zyxel Wx5610-B0 Firmware

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