VDB-185414 · CVE-2021-34583 · GCVE-0-2021-34583

CODESYS V2 Web Server prior 1.1.9.22 Web Request heap-based overflow

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.
6.7	$0-$5k	0.00

Summaryinfo

A vulnerability described as critical has been identified in CODESYS V2 Web Server. This impacts an unknown function of the component Web Request Handler. Such manipulation leads to heap-based overflow. This vulnerability is traded as CVE-2021-34583. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in CODESYS V2 Web Server (Web Server) and classified as critical. Affected by this issue is an unknown code block of the component Web Request Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is availability.

The weakness was shared 10/26/2021. The advisory is available at customers.codesys.com. This vulnerability is handled as CVE-2021-34583 since 06/10/2021. The technical details are unknown and an exploit is not available.

Upgrading to version 1.1.9.22 eliminates this vulnerability.

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Productinfo

Type

Web Server

Vendor

CODESYS

Name

V2 Web Server

License

commercial

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 7.5
CNA Vector (CERT@VDE): 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
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: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: V2 Web Server 1.1.9.22

Timelineinfo

06/10/2021 🔍
10/26/2021 +138 days 🔍
10/26/2021 +0 days 🔍
08/15/2025 +1389 days 🔍

Sourcesinfo

Advisory: customers.codesys.com
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-34583 (🔍)
GCVE (CVE): GCVE-0-2021-34583
GCVE (VulDB): GCVE-100-185414

Entryinfo

Created: 10/26/2021 15:28
Updated: 08/15/2025 23:03
Changes: 10/26/2021 15:28 (49), 10/30/2021 15:34 (2), 10/30/2021 15:40 (7), 08/15/2025 23:03 (26)
Complete: 🔍
Cache ID: 216::103