CVE-2021-21002— Denial of Service in Phoenix Contact FL COMSERVER UNI products
Quick assessment
Affected
Phoenix Contact FL COMSERVER
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Phoenix Contact FL COMSERVER UNI是德国Phoenix Contac（Phoenix Contact）公司的一个接口转换器。用于将串行 232/422/485 接口转换为以太网的串行设备服务器 Phoenix Contact FL COMSERVER UNI 存在安全漏洞，该漏洞源于在Phoenix Contact FL COMSERVER UNI版本< 2.40中，一个无效的Modbus异常响应可能会导致暂时拒绝服务。
Possible ATT&CK Techniques 1 AI
T1499 · Endpoint Denial of Service
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I. Basic Information for CVE-2021-21002
Vulnerability Information
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Vulnerability Title
Denial of Service in Phoenix Contact FL COMSERVER UNI products
Source: CVE Program / CVE List V5
Vulnerability Description
In Phoenix Contact FL COMSERVER UNI in versions < 2.40 a invalid Modbus exception response can lead to a temporary denial of service.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
对已超过有效生命周期的资源丧失索引
Source: CVE Program / CVE List V5
Vulnerability Title
Phoenix Contact FL COMSERVER UNI 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Phoenix Contact FL COMSERVER UNI是德国Phoenix Contac（Phoenix Contact）公司的一个接口转换器。用于将串行 232/422/485 接口转换为以太网的串行设备服务器 Phoenix Contact FL COMSERVER UNI 存在安全漏洞，该漏洞源于在Phoenix Contact FL COMSERVER UNI版本< 2.40中，一个无效的Modbus异常响应可能会导致暂时拒绝服务。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Phoenix Contact | FL COMSERVER | UNI 232/422/485 (2313452) ~ 2.40 | - |
|
II. Public POCs for CVE-2021-21002
| # | POC Description | Source Link | Shenlong Link |
|---|
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Other References for CVE-2021-21002 (1)
-
https://cert.vde.com/en-us/advisories/vde-2021-022 x_refsource_CONFIRM
Same Patch Batch · Phoenix Contact · 2021-06-25 · 7 CVEs total
| CVE-2021-33542 | 7.8 HIGH | Phoenix Contact: Automation Worx Software Suite affected by Remote Code Execution (RCE) vu |
| CVE-2021-21005 | 7.5 HIGH | Race Condition Vulnerability in Phoenix Contact FL SWITCH SMCS series products |
| CVE-2021-33541 | 7.5 HIGH | Phoenix Contact: ILC1x Industrial controllers affected by Denial-of-Service vulnerability |
| CVE-2021-21004 | 7.4 HIGH | Cross-site Scripting Vulnerability in Phoenix Contact FL SWITCH SMCS series products |
| CVE-2021-33540 | 7.3 HIGH | Phoenix Contact: Undocumented FTP acces in certain AXL F BK and IL BK devices |
| CVE-2021-21003 | 5.3 MEDIUM | Denial of Service Vulnerability in Phoenix Contact FL SWITCH SMCS series products |
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V. Comments for CVE-2021-21002
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