CVE-2021-1285

highpriority · track · 1EPSS 0.029 · 87 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
2.94% (87th) EPSS
CVSS 7.4 · high
Is it mine?
28 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · 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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.4
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.07.4highCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:Xsecondary · ENISA EU
v3.07.4highCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 2.8 · impact 4
v3.07.4highCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
v3.17.4highAV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

05

affected products (28)

Products and version ranges known to be affected.

06

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.

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

published 2024-11-18modified 2026-06-17
09

references (6)

External citations — patches, advisories, analysis.

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