CVE-2025-20311
Description
A vulnerability in the handling of certain Ethernet frames in Cisco IOS XE Software for Catalyst 9000 Series Switches could allow an unauthenticated, adjacent attacker to cause an egress port to become blocked and drop all outbound traffic. This vulnerability is due to improper handling of crafted Ethernet frames. An attacker could exploit this vulnerability by sending crafted Ethernet frames through an affected switch. A successful exploit could allow the attacker to cause the egress port to which the crafted frame is forwarded to start dropping all frames, resulting in a denial of service (DoS) condition.
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| cisco ios_xe | 16.6.1, 16.6.2, 16.6.3, 16.6.4, 16.6.4a, 16.6.5, 16.6.6, 16.6.7, 16.6.8, 16.6.9, 16.6.10, 16.7.1, 16.8.1, 16.8.1a, 16.8.1s, 16.9.1, 16.9.1s, 16.9.2, 16.9.3, 16.9.4, 16.9.5, 16.9.6, 16.9.7, 16.9.8, 16.10.1, 16.10.1e, 16.10.1s, 16.11.1, 16.11.1b, 16.11.1s, 16.12.1, 16.12.1c, 16.12.1s, 16.12.2, 16.12.2s, 16.12.3, 16.12.3a, 16.12.3s, 16.12.4, 16.12.4a, 16.12.5, 16.12.5b, 16.12.6, 16.12.6a, 16.12.7, 16.12.8, 16.12.14, 17.1.1, 17.1.1s, 17.1.1t, 17.1.3, 17.2.1, 17.2.1a, 17.3.1, 17.3.2, 17.3.2a, 17.3.3, 17.3.4, 17.3.4b, 17.3.5, 17.3.6, 17.3.7, 17.3.8, 17.3.8a, 17.4.1, 17.5.1, 17.6.1, 17.6.1y, 17.6.2, 17.6.3, 17.6.4, 17.6.5, 17.6.5a, 17.6.6, 17.6.6a, 17.6.7, 17.6.8, 17.7.1, 17.8.1, 17.9.1, 17.9.2, 17.9.3, 17.9.4, 17.9.4a, 17.9.5, 17.9.6, 17.9.6a, 17.10.1, 17.10.1b, 17.11.1, 17.11.99sw, 17.12.1, 17.12.1z3, 17.12.2, 17.12.3, 17.12.4, 17.13.1, 17.14.1, 17.15.1, 17.15.2, 17.15.2a, 17.15.2b, 17.16.1 | — |
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