CVE-2020-3119 | Cisco NX-OS Software Cisco Discovery Protocol Remote Code Execution Vulnerability

A vulnerability in the Cisco Discovery Protocol implementation for Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a reload on an affected device. The vulnerability exists because the Cisco Discovery Protocol parser does not properly validate input for certain fields in a Cisco Discovery Protocol message. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. An successful exploit could allow the attacker to cause a stack overflow, which could allow the attacker to execute arbitrary code with administrative privileges on an affected device. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

Published: 2020-02-05 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-3119 is rated Moderate Risk (62.3/100): CVSS High severity, with high exploitation likelihood (EPSS 7.91%, 92th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-3119

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 12.99% 7.91% -5.07%
2 2025-11-18 7.87% 12.99% +5.12%
3 2025-03-30 7.87%

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-3119

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
8.8 3.0 HIGH
CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
8.3 2.0 HIGH
AV:A/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
6.5 10.0 [email protected]

Weakness enumeration for CVE-2020-3119

Affected software / configurations for CVE-2020-3119

Vendor Product Version Raw CPE
cisco nx-os >= 7.0\(3\)f2, < 9.3\(2\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os >= 7.0\(3\)i, < 7.0\(3\)i7\(8\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os >= 7.1, < 7.3\(6\)n1\(1\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os < 9.3\(2\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os >= 14.0, < 14.2\(1j\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco ucs_manager < 3.2\(3m\) cpe:2.3:a:cisco:ucs_manager:*:*:*:*:*:*:*:*
cisco ucs_manager >= 4.0, < 4.0\(4f\) cpe:2.3:a:cisco:ucs_manager:*:*:*:*:*:*:*:*

References for CVE-2020-3119

cvelogic Threat Intelligence