VDB-359144 · CVE-2026-35225 · vde-2026-040

CODESYS EtherNetIP 4.1.0.0 TCP Connection unusual condition

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.
5.1	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in CODESYS EtherNetIP. Impacted is an unknown function of the component TCP Connection Handler. Such manipulation leads to unusual condition. This vulnerability is traded as CVE-2026-35225. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in CODESYS EtherNetIP. It has been rated as problematic. Affected by this issue is some unknown functionality of the component TCP Connection Handler. The manipulation with an unknown input leads to a unusual condition vulnerability. Using CWE to declare the problem leads to CWE-754. The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. Impacted is availability. CVE summarizes:

An unauthenticated remote attacker is able to exhaust all available TCP connections in the CODESYS EtherNet/IP adapter stack, preventing legitimate clients from establishing new connections.

The advisory is shared for download at codesys.csaf-tp.certvde.com. This vulnerability is handled as CVE-2026-35225 since 04/01/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 4.9.0.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25222). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

CODESYS

Name

EtherNetIP

Version

4.1.0.0

License

commercial

CPE 2.3info

🔒

CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

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

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: Unusual condition
CWE: CWE-754
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: EtherNetIP 4.9.0.0

Timelineinfo

04/01/2026 CVE reserved
04/23/2026 +22 days Advisory disclosed
04/23/2026 +0 days VulDB entry created
04/23/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: vde-2026-040
Status: Confirmed

CVE: CVE-2026-35225 (🔒)
GCVE (CVE): GCVE-0-2026-35225
GCVE (VulDB): GCVE-100-359144
EUVD: 🔒

Entryinfo

Created: 04/23/2026 17:53
Updated: 04/23/2026 18:12
Changes: 04/23/2026 17:53 (67), 04/23/2026 18:12 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.