How severe is CVE-2020-3512?

CVE-2020-3512 has a CVSS 3.x base score of 7.4, rated high 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-2020-3512 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3512?

CVE-2020-3512 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3512?

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-2020-3512 published?

CVE-2020-3512 was published on 2020-09-24 and last updated on 2026-06-17.

CVE-2020-3512

CVE-2020-3512 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 7.4. 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-400.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 5.7
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Cisco Ios Xe
Published: 2020-09-24
Last modified: 2026-06-17

Description

A vulnerability in the PROFINET handler for Link Layer Discovery Protocol (LLDP) messages of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a crash on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of LLDP messages in the PROFINET LLDP message handler. An attacker could exploit this vulnerability by sending a malicious LLDP message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.

Frequently asked questions

What is CVE-2020-3512?: A vulnerability in the PROFINET handler for Link Layer Discovery Protocol (LLDP) messages of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a crash on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of LLDP messages in the PROFINET LLDP message handler. An attacker could exploit this vulnerability by sending a malicious LLDP message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.
How severe is CVE-2020-3512?: CVE-2020-3512 has a CVSS 3.x base score of 7.4, rated high 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-2020-3512 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3512?: CVE-2020-3512 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3512?: 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-2020-3512 published?: CVE-2020-3512 was published on 2020-09-24 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-profinet-dos-65qYG3W5

Affected products (1)

cpe:2.3:o:cisco:ios_xe:15.2\(7\)e:*:*:*:*:*:*:*

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