CVE-2026-20067Multiple Cisco Products Snort 3 TBD Denial of Service Vulnerability
- 5.8MediumCVSS base score
- 0.52%Exploitation in 30 daysEPSS · top 56% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Multiple Cisco products are affected by a vulnerability in the Snort 3 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 parsing the Multicast DNS fields of the HTTP header. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine unexpectedly restarts.
Timeline
ID reserved
By cisco
- 5 months later
· 5 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.1 | Medium5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L |
| NVDNVD · Analyzed | 3.1 | Medium5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L |
- EPSS (exploitation in 30 days)
- 0.52% · top 56% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.8.
Affected products
- affected 3.0.0
- affected 3.0.2
- affected 3.0.3
- affected 3.0.1
- affected 3.1.0
- affected 3.0.4
- affected 3.1.1
- affected 3.1.2
- affected 3.2.0
- affected 3.0.5
- affected 3.2.1
- affected 3.0.6
- affected 3.2.2
- affected 3.2.3
- affected 3.2.4
- affected 4.0.0
- affected 4.0.1
- affected 4.0.2
- affected 4.0.3
- affected 4.1.0
- affected 4.1.1
- affected 4.1.2
- affected 4.1.3
- affected 4.1.4
- affected 4.2.0
- affected 4.2.1
- affected 4.1.5
- affected 4.2.2
- affected 4.2.X
- affected 4.2.3
- affected 4.2.4
- affected 4.2.6
- affected 4.1.6
- affected 4.3.0
- affected 4.3.1
- affected 4.3.2
- affected 4.3.3
- affected 4.4.0
- affected 4.4.1
- affected 4.4.2
- and 14 more
Cisco · Cisco Secure Firewall Threat Defense (FTD) Software
- affected 7.0.0
- affected 7.0.0.1
- affected 7.0.1
- affected 7.1.0
- affected 7.0.1.1
- affected 7.1.0.1
- affected 7.0.2
- affected 7.2.0
- affected 7.0.2.1
- affected 7.0.3
- affected 7.1.0.2
- affected 7.2.0.1
- affected 7.0.4
- affected 7.2.1
- affected 7.0.5
- affected 7.3.0
- affected 7.2.2
- affected 7.2.3
- affected 7.3.1
- affected 7.1.0.3
- affected 7.2.4
- affected 7.0.6
- affected 7.2.5
- affected 7.2.4.1
- affected 7.3.1.1
- affected 7.4.0
- affected 7.0.6.1
- affected 7.2.5.1
- affected 7.4.1
- affected 7.2.6
- affected 7.0.6.2
- affected 7.4.1.1
- affected 7.2.7
- affected 7.2.5.2
- affected 7.3.1.2
- affected 7.2.8
- affected 7.6.0
- affected 7.4.2
- affected 7.2.8.1
- affected 7.0.6.3
- and 17 more
Cisco · Cisco UTD SNORT IPS Engine Software
- affected 17.3.1a
- affected 17.2.1r
- affected 17.3.2
- affected 17.4.1a
- affected 17.5.1
- affected 17.3.3
- affected 17.5.1a
- affected 17.3.4
- affected 17.3.4a
- affected 17.4.2
- affected 17.4.1b
- affected 17.6.1a
- affected 17.7.1a
- affected 17.6.2
- affected 17.8.1a
- affected 17.3.5
- affected 17.6.3
- affected 17.6.3a
- affected 17.7.2
- affected 17.9.1a
- affected 17.6.4
- affected 17.10.1a
- affected 17.3.6
- affected 17.3.7
- affected 17.9.2a
- affected 17.6.5
- affected 17.11.1a
- affected 17.9.3a
- affected 17.12.1a
- affected 17.9.4
- affected 17.6.6
- affected 17.3.8
- affected 17.3.8a
- affected 17.6.6a
- affected 17.9.4a
- affected 17.12.2
- affected 17.13.1a
- affected 17.9.5a
- affected 17.12.3
- affected 17.6.7
- and 31 more
What to do
Exploitation: The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-9466 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-20067)Record last updated .