VDB-246382 · CVE-2023-35138 · GCVE-0-2023-35138

Zyxel NAS326/NAS542 HTTP POST Request show_zysync_server_contents os command injection

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.8	$5k-$25k	0.00

Summaryinfo

A vulnerability labeled as critical has been found in Zyxel NAS326 and NAS542. This issue affects the function show_zysync_server_contents of the component HTTP POST Request Handler. Executing a manipulation can lead to os command injection. This vulnerability is tracked as CVE-2023-35138. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Zyxel NAS326 and NAS542 (the affected version unknown). It has been declared as very critical. This vulnerability affects the function show_zysync_server_contents of the component HTTP POST Request Handler. The manipulation with an unknown input leads to a os command injection vulnerability. The CWE definition for the vulnerability is CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A command injection vulnerability in the “show_zysync_server_contents” function of the Zyxel NAS326 firmware version V5.21(AAZF.14)C0 and NAS542 firmware version V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands by sending a crafted HTTP POST request.

The weakness was disclosed 11/30/2023. The advisory is available at zyxel.com. This vulnerability was named CVE-2023-35138 since 06/14/2023. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 11/30/2023). This vulnerability is assigned to T1202 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

Zyxel

Name

License

commercial

Website

Vendor: https://www.zyxel.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 9.8

VulDB Base Score: 9.8
VulDB Temp Score: 9.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (Zyxel Corporation): 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Os command injection
CWE: CWE-78 / CWE-77 / CWE-74
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/14/2023 🔍
11/30/2023 +169 days 🔍
11/30/2023 +0 days 🔍
11/30/2023 +0 days 🔍

Sourcesinfo

Vendor: zyxel.com

Advisory: zyxel.com
Status: Confirmed

CVE: CVE-2023-35138 (🔍)
GCVE (CVE): GCVE-0-2023-35138
GCVE (VulDB): GCVE-100-246382

Entryinfo

Created: 11/30/2023 06:49
Changes: 11/30/2023 06:49 (48)
Complete: 🔍
Cache ID: 216::103