Cyber Resilience

CVE-2021-35033

HighPublic PoC

Published: 23 November 2021

Published
23 November 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0011 29.7th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-35033 is a high-severity Password in Configuration File (CWE-260) vulnerability in Zyxel Nbg6818 Firmware. Its CVSS base score is 7.8 (High).

Operationally, ranked at the 29.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

A vulnerability in specific versions of Zyxel NBG6818, NBG7815, WSQ20, WSQ50, WSQ60, and WSR30 firmware with pre-configured password management could allow an attacker to obtain root access of the device, if the local attacker dismantles the device and uses a…

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USB-to-UART cable to connect the device, or if the remote assistance feature had been enabled by an authenticated user.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

zyxel
nbg6818 firmware
≤ 1.00\(absc.5\)c0
zyxel
nbg7815 firmware
≤ 1.00\(absk.7\)c0
zyxel
wsq20 firmware
≤ 1.00\(abof.11\)c0
zyxel
wsq50 firmware
≤ 2.20\(abkj.7\)c0
zyxel
wsq60 firmware
≤ 2.20\(abnd.8\)c0
zyxel
wsr30 firmware
≤ 1.00\(abmy.12\)c0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-287

Detects unauthorized successful logons resulting from improper authentication implementations.

addresses: CWE-287

Documented procedures ensure personnel are trained on authentication mechanisms, tangibly lowering the risk of improper authentication being exploited.

addresses: CWE-287

Security awareness training instructs users on secure authentication practices and avoiding credential compromise.

addresses: CWE-287

Training on authentication mechanisms and best practices decreases the occurrence of improper authentication.

addresses: CWE-287

Non-repudiation requires strong authentication mechanisms to irrefutably attribute performed actions to specific individuals or processes.

addresses: CWE-287

Session content review can reveal authentication bypasses or failures in session establishment.

addresses: CWE-287

Review of authentication-related audit records can detect improper authentication mechanisms or bypasses.

addresses: CWE-287

Assessments check authentication mechanisms for correct implementation and effectiveness, reducing successful authentication bypass attempts.

References