Buffer overflow in Cisco Cyber Vision

CVE-2026-20067

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.

Vulnerability class: Buffer Overflow

EPSS: 0.005 (37.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-20067?
CVE-2026-20067 is a medium-severity vulnerability in Cisco Cyber Vision, classified under Out-of-bounds Write. CVSS score: 5.8/10. Published 2026-03-04.
How severe is CVE-2026-20067?
Medium severity. CVSS v3 base score is 5.8 out of 10.