CVE-2020-3118
highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.117 · 96 %ileEURUUSadded 2021-11-03remediate by 2022-05-03
required action Apply updates per vendor instructions.
EPSS · scored 2026-10-23
Cisco IOS XR Software Discovery Protocol Format String Vulnerability
A 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).
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco IOS XR Softwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (11)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20200205-iosxr-cdp-rceCisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability2020-02-05csaf · cisco_csafUS
A 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. Note: 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). Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-iosxr-cdp-rce ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-iosxr-cdp-rce"]
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (19)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/45786cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3118cnnvd
- https://packetstormsecurity.com/files/156203/Cisco-Discovery-Protocol-CDP-Remote-Device-Takeover.htmlcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-fxnxos-iosxr-cdp-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-iosxr-cdp-rcecnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-ipcameras-rce-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-nxos-cdp-rcecnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-voip-phones-rce-doscnnvd
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