CVE-2021-1285
highpriority · track · 1EPSS 0.029 · 87 %ileEURUUSEPSS · scored 2026-10-27
Multiple Cisco products are affected by a vulnerability in the Ethernet Frame Decoder of the Snort detection engine that could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper handling of error conditions when processing Ethernet frames. An attacker could exploit this vulnerability by sending malicious Ethernet frames through an affected device. A successful exploit could allow the attacker to exhaust disk space on the affected device, which could result in administrators being unable to log in to the device or the device being unable to boot up correctly.Note: Manual intervention is required to recover from this situation. Customers are advised to contact the Cisco Technical Assistance Center (TAC) to help recover a device in this condition.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco UTD SNORT IPS Engine 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 (28)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-snort-ethernet-dos-HGXgJH8nMultiple Cisco Products Snort Ethernet Frame Decoder Denial of Service Vulnerability2021-03-03csaf · cisco_csafUS
Multiple Cisco products are affected by a vulnerability in the Ethernet Frame Decoder of the Snort detection engine that could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper handling of error conditions when processing Ethernet frames. An attacker could exploit this vulnerability by sending malicious Ethernet frames through an affected device. A successful exploit could allow the attacker to exhaust disk space on the affected device, which could result in administrators being unable to log in to the device or the device being unable to boot up correctly. Note: Manual intervention is required to recover from this situation. Customers are advised to contact the Cisco Technical Assistance Center (TAC) to help recover a device in this condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-ethernet-dos-HGXgJH8ncnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-ethernet-dos-HGXgJH8ncnnvd
- https://vigilance.fr/vulnerability/Snort-denial-of-service-via-Ethernet-Frame-Decoder-34752cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.0782cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-ethernet-dos-HGXgJH8nenisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-ethernet-dos-HGXgJH8nnvd
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