Description
Multiple Cisco products are affected by a vulnerability in the Snort 3 NetFlow Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection.
This vulnerability is due to incomplete error checking when Snort 3 parses UDP Netflow Protocol packets. An attacker could exploit this vulnerability by sending a single crafted Netflow packet through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a DoS condition.
This vulnerability is due to incomplete error checking when Snort 3 parses UDP Netflow Protocol packets. An attacker could exploit this vulnerability by sending a single crafted Netflow packet through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a DoS condition.
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
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| Cisco | Cisco Open Source Snort3 | unknown |
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| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | unknown |
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| Cisco | Cisco UTD SNORT IPS Engine Software | unknown |
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No data available yet.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
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References
History
Wed, 21 Oct 2026 17:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Multiple Cisco products are affected by a vulnerability in the Snort 3 NetFlow Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to incomplete error checking when Snort 3 parses UDP Netflow Protocol packets. An attacker could exploit this vulnerability by sending a single crafted Netflow packet through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a DoS condition. | |
| Title | Multiple Cisco Products Snort 3 Netflow Denial of Service Vulnerabilities | |
| Weaknesses | CWE-835 | |
| References |
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| Metrics |
cvssV3_1
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Subscriptions
No data.
MITRE
Status: PUBLISHED
Assigner: cisco
Published:
Updated: 2026-10-21T16:12:20.285Z
Reserved: 2025-10-08T11:59:15.351Z
Link: CVE-2026-20019
Vulnrichment
No data.
NVD
Status : Awaiting Analysis
Published: 2026-10-21T17:18:26.890
Modified: 2026-10-21T18:54:37.403
Link: CVE-2026-20019
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-10-21T21:30:15Z
Weaknesses