Description
A buffer overflow vulnerability in the URL parser of the zhttpd web server in Zyxel VMG8825-T50K firmware versions prior to V5.50(ABOM.5)C0 could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and potentially execute arbitrary code by sending a specially crafted HTTP request.
Published: 2025-07-16
Score: 9.8 Critical
EPSS: 1.4% Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories
Source ID Title
EUVD EUVD EUVD-2025-21579 A buffer overflow vulnerability in the URL parser of the zhttpd web server in Zyxel VMG8825-T50K firmware versions prior to V5.50(ABOM.5)C0 could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and potentially execute arbitrary code by sending a specially crafted HTTP request.
History

Wed, 14 Jan 2026 18:00:00 +0000

Type Values Removed Values Added
First Time appeared 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 ex3510-b0
Zyxel ex3510-b0 Firmware
Zyxel ex5510-b0
Zyxel ex5510-b0 Firmware
Zyxel vmg1312-t20b
Zyxel vmg1312-t20b Firmware
Zyxel vmg3625-t50b
Zyxel vmg3625-t50b Firmware
Zyxel vmg3925-b10b
Zyxel vmg3925-b10b Firmware
Zyxel vmg3925-b10c
Zyxel vmg3925-b10c Firmware
Zyxel vmg3927-b50a
Zyxel vmg3927-b50a Firmware
Zyxel vmg3927-b50b
Zyxel vmg3927-b50b Firmware
Zyxel vmg3927-b60a
Zyxel vmg3927-b60a Firmware
Zyxel vmg3927-t50k
Zyxel vmg3927-t50k Firmware
Zyxel vmg4005-b50b
Zyxel vmg4005-b50b Firmware
Zyxel vmg4927-b50a
Zyxel vmg4927-b50a Firmware
Zyxel vmg8623-t50b
Zyxel vmg8623-t50b Firmware
Zyxel vmg8825-b50a
Zyxel vmg8825-b50a Firmware
Zyxel vmg8825-b60a
Zyxel vmg8825-b60a Firmware
Zyxel vmg8825-bx0b
Zyxel vmg8825-bx0b Firmware
Zyxel vmg8825-t50k
Zyxel vmg8924-b10d
Zyxel vmg8924-b10d Firmware
Zyxel xmg3927-b50a
Zyxel xmg3927-b50a Firmware
Zyxel xmg8825-b50a
Zyxel xmg8825-b50a Firmware
CPEs cpe:2.3:h:zyxel:emg3525-t50b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:emg5523-t50b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:emg5723-t50k:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:emg6726-b10a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:ex3510-b0:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:ex5510-b0:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg1312-t20b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3625-t50b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3925-b10b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3925-b10c:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3927-b50a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3927-b50b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3927-b60a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg3927-t50k:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg4005-b50b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg4927-b50a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg8623-t50b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg8825-b50a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg8825-b60a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg8825-bx0b:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg8825-t50k:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:vmg8924-b10d:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:xmg3927-b50a:-:*:*:*:*:*:*:*
cpe:2.3:h:zyxel:xmg8825-b50a:-:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:emg3525-t50b_firmware:*:*:*:*:america:*:*:*
cpe:2.3:o:zyxel:emg3525-t50b_firmware:*:*:*:*:emea:*:*:*
cpe:2.3:o:zyxel:emg5523-t50b_firmware:*:*:*:*:america:*:*:*
cpe:2.3:o:zyxel:emg5523-t50b_firmware:*:*:*:*:emea:*:*:*
cpe:2.3:o:zyxel:emg5723-t50k_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:emg6726-b10a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:ex3510-b0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:ex5510-b0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg1312-t20b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3625-t50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3925-b10b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3925-b10c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3927-b50a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3927-b50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3927-b60a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3927-t50k_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg4005-b50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg4927-b50a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8623-t50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8825-b50a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8825-b60a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8825-bx0b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8825-t50k_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8924-b10d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:xmg3927-b50a_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:xmg8825-b50a_firmware:*:*:*:*:*:*:*:*
Vendors & Products 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 ex3510-b0
Zyxel ex3510-b0 Firmware
Zyxel ex5510-b0
Zyxel ex5510-b0 Firmware
Zyxel vmg1312-t20b
Zyxel vmg1312-t20b Firmware
Zyxel vmg3625-t50b
Zyxel vmg3625-t50b Firmware
Zyxel vmg3925-b10b
Zyxel vmg3925-b10b Firmware
Zyxel vmg3925-b10c
Zyxel vmg3925-b10c Firmware
Zyxel vmg3927-b50a
Zyxel vmg3927-b50a Firmware
Zyxel vmg3927-b50b
Zyxel vmg3927-b50b Firmware
Zyxel vmg3927-b60a
Zyxel vmg3927-b60a Firmware
Zyxel vmg3927-t50k
Zyxel vmg3927-t50k Firmware
Zyxel vmg4005-b50b
Zyxel vmg4005-b50b Firmware
Zyxel vmg4927-b50a
Zyxel vmg4927-b50a Firmware
Zyxel vmg8623-t50b
Zyxel vmg8623-t50b Firmware
Zyxel vmg8825-b50a
Zyxel vmg8825-b50a Firmware
Zyxel vmg8825-b60a
Zyxel vmg8825-b60a Firmware
Zyxel vmg8825-bx0b
Zyxel vmg8825-bx0b Firmware
Zyxel vmg8825-t50k
Zyxel vmg8924-b10d
Zyxel vmg8924-b10d Firmware
Zyxel xmg3927-b50a
Zyxel xmg3927-b50a Firmware
Zyxel xmg8825-b50a
Zyxel xmg8825-b50a Firmware

Wed, 16 Jul 2025 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00729}


Wed, 16 Jul 2025 07:15:00 +0000

Type Values Removed Values Added
Description A buffer overflow vulnerability in the URL parser of the zhttpd web server in Zyxel VMG8825-T50K firmware versions prior to V5.50(ABOM.5)C0 could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and potentially execute arbitrary code by sending a specially crafted HTTP request.
Weaknesses CWE-120
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}


Subscriptions

Zyxel Emg3525-t50b Emg3525-t50b Firmware Emg5523-t50b Emg5523-t50b Firmware Emg5723-t50k Emg5723-t50k Firmware Emg6726-b10a Emg6726-b10a Firmware Ex3510-b0 Ex3510-b0 Firmware Ex5510-b0 Ex5510-b0 Firmware Vmg1312-t20b Vmg1312-t20b Firmware Vmg3625-t50b Vmg3625-t50b Firmware Vmg3925-b10b Vmg3925-b10b Firmware Vmg3925-b10c Vmg3925-b10c Firmware Vmg3927-b50a Vmg3927-b50a Firmware Vmg3927-b50b Vmg3927-b50b Firmware Vmg3927-b60a Vmg3927-b60a Firmware Vmg3927-t50k Vmg3927-t50k Firmware Vmg4005-b50b Vmg4005-b50b Firmware Vmg4927-b50a Vmg4927-b50a Firmware Vmg8623-t50b Vmg8623-t50b Firmware Vmg8825-b50a Vmg8825-b50a Firmware Vmg8825-b60a Vmg8825-b60a Firmware Vmg8825-bx0b Vmg8825-bx0b Firmware Vmg8825-t50k Vmg8825-t50k Firmware Vmg8924-b10d Vmg8924-b10d Firmware Xmg3927-b50a Xmg3927-b50a Firmware Xmg8825-b50a Xmg8825-b50a Firmware
cve-icon MITRE

Status: PUBLISHED

Assigner: Zyxel

Published:

Updated: 2026-02-26T17:50:32.365Z

Reserved: 2025-07-15T02:01:55.637Z

Link: CVE-2025-7673

cve-icon Vulnrichment

Updated: 2025-07-16T14:35:11.324Z

cve-icon NVD

Status : Analyzed

Published: 2025-07-16T07:15:24.437

Modified: 2026-01-14T17:52:29.083

Link: CVE-2025-7673

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2025-07-21T15:17:38Z

Weaknesses