CVE-2020-24685
An unauthenticated specially crafted packet sent by an attacker over the network will cause a denial-of-service (DoS) vulnerability.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.61%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- EPSS
- 1.61% probability · 76th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-789, CWE-770
- Affected
- abb/ac500 cpu firmware
- Source
- cybersecurity@ch.abb.com
EPSS 1.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.