CVE-2026-12489

Medium

Description

An incorrect authorization vulnerability in the Data Access Layer (DAL) of Zyxel EX3501-T0 firmware versions through 5.44(ACHR.6)C0 could allow an authenticated attacker to escalate privileges by modifying the login_privilege data on an affected device.

SeverityMedium

CVSS6.5

Exploit probability—

Product

EX3501-T0 firmware

PublishedOct 20, 2026

First seenOct 20, 2026

Weakness typeCWE-863Incorrect authorization

How to fix

Vendor advisories

zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-incorrect-authorization-vulnerability-in-the-dal-of-certain-5g-nr-cpe-dsl-ethernet-cpe-fiber-onts-and-wireless-extenders-10-20-2026

Affected products

Product	Affected versions	Fixed in
Zyxel EX3501-T0 firmware	<= 5.44(ACHR.6)C0	—

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