CVE-2020-24685: abb ac500_cpu_firmware
Vulnerability summary
CVE-2020-24685 is a high (CVSS 8.6) vulnerability in abb ac500_cpu_firmware. EPSS estimates a 1.61% chance of exploitation in the next 30 days, higher than 75.6% of scored vulnerabilities.
Timeline
- 09-02-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
An unauthenticated specially crafted packet sent by an attacker over the network will cause a denial-of-service (DoS) vulnerability. Vulnerability allows attacker to stop the PLC. After stopping (ERR LED flashing red), physical access to the PLC is required in order to restart the application. This issue affects: ABB AC500 V2 products with onboard Ethernet version 2.8.4 and prior versions.
CVSS metrics
3 scores · 2 sources · 2 versions- NVDNIST8.6HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS trend
Probability
1.61%
Chance of exploitation in the next 30 days
Percentile
76%
Versus all other CVEs
30-day change
0.00 pp
From 1.61% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-789Memory Allocation with Excessive Size ValueThe product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.
- CWE-770Allocation of Resources Without Limits or ThrottlingThe product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Affected systems
Abb2 products
- ac500_cpu_firmware< 2.8.5
- ac500 v2 products with onboard ethernetversion 2.8.4 and prior versions
1 vendor · 2 products