CVE-2020-24685
CVE-2020-24685 is a high-severity vulnerability in Abb Ac500 Cpu Firmware with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (73rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-770
- Affected product: Abb Ac500 Cpu Firmware
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2020-24685?
- 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.
- How severe is CVE-2020-24685?
- CVE-2020-24685 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2020-24685 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-24685?
- CVE-2020-24685 affects Abb Ac500 Cpu Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-24685?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-24685 published?
- CVE-2020-24685 was published on 2021-02-09 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:abb:ac500_cpu_firmware:*:*:*:*:*:*:*:*
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