CVE-2020-24686 - CVE House
Back to Database
Status published High CVE-2020-24686

AC500 V2 webserver denial of service vulnerability

Vulnerability Description

The vulnerabilities can be exploited to cause the web visualization component of the PLC to stop and not respond, leading to genuine users losing remote visibility of the PLC state. If a user attempts to login to the PLC while this vulnerability is exploited, the PLC will show an error state and refuse connections to Automation Builder. The execution of the PLC application is not affected by this vulnerability. This issue affects ABB AC500 V2 products with onboard Ethernet.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2020-24686

Credits & Attribution

No credits recorded in the NVD database.

References

More from ABB

View All →
CVE-2025-9970
Application credential stored in clear text in memory
Medium 5.7
CVE-2025-9574
Missing Authentication Vulnerability
Critical 9.9
CVE-2025-8754
ABB AbilityTM zenon Remote Transport Vulnerability
High 8.7
CVE-2025-7745
Modbus TCP buffer overread
Medium 6.9
CVE-2025-7705
Authentication bypass due to compatibility mode enabled by default
High 8.6

Affected Vendor

Affected Software

AC500 V2 products with onboard Ethernet
Vulnerable Versions:
All

Timeline

Official Publish: February 26th, 2021
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-400

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact