Answer in brief
CVE-2020-3118 records a High severity vulnerability in Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability. The current sources mark it as known exploited. The current feed maps Cisco/Cisco IOS XR Software (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. Known-exploitation status makes exposure review time-sensitive. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Cisco/Cisco IOS XR Software (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Cisco/Cisco IOS XR Softwaregeneric | >=unspecified <6.6.3 | 6.6.3 |
Published upstream
Feb 5, 2020
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2025
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
May 24, 2026
Added to CISA KEV
Nov 3, 2021
Evidence: source:kev:kev:kev:recordA vulnerability in the Cisco Discovery Protocol implementation for Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a reload on an affected device. The vulnerability is due to improper validation of string input from certain fields in Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A 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).
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2020-3118 records a High severity vulnerability in Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability. The current sources mark it as known exploited. The current feed maps Cisco/Cisco IOS XR Software (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. Known-exploitation status makes exposure review time-sensitive. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Cisco/Cisco IOS XR Software (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Cisco/Cisco IOS XR Softwaregeneric | >=unspecified <6.6.3 | 6.6.3 |
Published upstream
Feb 5, 2020
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2025
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
May 24, 2026
Added to CISA KEV
Nov 3, 2021
Evidence: source:kev:kev:kev:recordA vulnerability in the Cisco Discovery Protocol implementation for Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a reload on an affected device. The vulnerability is due to improper validation of string input from certain fields in Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A 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).
Quoted source text, attributed separately from HOL analysis.