No exploitation reported

CVE-2021-1285

No exploitation reported by the sources we read.

Published2024-11-18
WeaknessCWE-770

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC

2024-11-1816:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-1285?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-1285?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2021-1285 yet.

Full record on NVD

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVE recordread 2026-10-23
CISA-ADPSSVC decisionnone2024-11-18
OpenCVESSVC decisionnone—
CNACVSS 3.07.4read 2026-10-23
CNAweakness (CWE)CWE-770read 2026-10-23
FIRST EPSSEPSS score2.9 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Published: 2024-11-18
Last Modified: 2026-06-17
NVD status: Deferred

Frequently asked questions

What is CVE-2021-1285?

Is CVE-2021-1285 actively exploited?

Active exploitation of CVE-2021-1285 has not been confirmed. Its EPSS score was 2.9% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-1285?

CVE-2021-1285 has a CVSS v3 base score of 7.4 (HIGH severity), with vector string CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.

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