CVE-2026-20019 json
Multiple Cisco Products Snort 3 Netflow Denial of Service Vulnerabilities
published 2026-10-21 18 d ago modified 2026-10-22 17 d ago also EUVD-2026-107371
- cvss
- 5.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 18 d ago
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L |
Affected products
- Cisco Cisco Open Source Snort3
- Cisco Cisco Secure Firewall Threat Defense (FTD) Software
- Cisco Cisco UTD SNORT IPS Engine Software
Classification
- Weakness
-
- CWE-835 Loop with Unreachable Exit Condition
References
Sources
- CVE List CVE-2026-20019
- NVD CVE-2026-20019
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