CVE-2020-12521
CVE-2020-12521 is a medium-severity vulnerability in Phoenixcontact Plcnext Firmware with a CVSS 3.x base score of 6.5. 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-20.
Key facts
- Severity: Medium (CVSS 3.x base score 6.5)
- CVSS v2: 6.1
- EPSS exploit prediction: 0% (36th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Phoenixcontact Plcnext Firmware
- Published:
- Last modified:
Description
On Phoenix Contact PLCnext Control Devices versions before 2021.0 LTS a specially crafted LLDP packet may lead to a high system load in the PROFINET stack. An attacker can cause failure of system services or a complete reboot.
Frequently asked questions
- What is CVE-2020-12521?
- On Phoenix Contact PLCnext Control Devices versions before 2021.0 LTS a specially crafted LLDP packet may lead to a high system load in the PROFINET stack. An attacker can cause failure of system services or a complete reboot.
- How severe is CVE-2020-12521?
- CVE-2020-12521 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2020-12521 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-12521?
- CVE-2020-12521 affects Phoenixcontact Plcnext Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-12521?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-12521 published?
- CVE-2020-12521 was published on 2020-12-17 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:phoenixcontact:plcnext_firmware:*:*:*:*:long_term_support:*:*:*
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- CVE-2020-12519 — High (CVSS 8.8): On Phoenix Contact PLCnext Control Devices versions before 2021.0 LTS an attacker can use this vulnerability i.e. to…
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