SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2021-32030

ASUS Routers Improper Authentication Vulnerability

KEVCRITICAL 9.8EPSS 99.4%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 23 June 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

The administrator application on ASUS GT-AC2900 devices before 3.0.0.4.386.42643 and Lyra Mini before 3.0.0.4_384_46630 allows authentication bypass when processing remote input from an unauthenticated user, leading to unauthorized access to the administrator interface. This relates to handle_request in router/httpd/httpd.c and auth_check in web_hook.o. An attacker-supplied value of '\0' matches the device's default value of '\0' in some situations. Note: All versions of Lyra Mini and earlier which are unsupported (End-of-Life, EOL) are also affected by this vulnerability, Consumers can mitigate this vulnerability by disabling the remote access features from WAN.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
99.39% probability · 100th percentile
CISA KEV
Listed 2 June 2025 · due 23 June 2025
Weakness
CWE-287
Affected
asus/lyra mini firmware · asus/gt-ac2900 firmware
Source
cve@mitre.org

CISA notes

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://www.asus.com/us/supportonly/lyra%20mini/helpdesk_bios/ ; https://www.asus.com/us/supportonly/rog%20rapture%20gt-ac2900/helpdesk_bios/; https://nvd.nist.gov/vuln/detail/CVE-2021-32030

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.