CVE-2021-1285: DoS (CVSS 7.4)

Description

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.

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CVSS v3.1 Score

7.4

HIGH

CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Weakness Type (CWE)

CWE-770 CWE-770

References

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-ethernet-dos-HGXgJH8n

Frequently Asked Questions

What is CVE-2021-1285? +

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. It has a CVSS v3.1 base score of 7.4 (HIGH).

How severe is CVE-2021-1285? +

CVE-2021-1285 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

How do I check if I'm vulnerable to CVE-2021-1285? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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