CVE-2025-20311 — Cisco IOS XE Software vulnerability
Severity
7.4HIGHNVD
EPSS
0.0%
top 91.05%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedSep 24
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 wh…
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:HExploitability: 2.8 | Impact: 4.0
Affected Packages1 packages
🔴Vulnerability Details
2GHSA▶
GHSA-pr4q-4px5-72j6: A vulnerability in the handling of certain Ethernet frames in Cisco IOS XE Software for Catalyst 9000 Series Switches could allow an unauthenticated,↗2025-09-24
CVEList▶
CVE-2025-20311: A vulnerability in the handling of certain Ethernet frames in Cisco IOS XE Software for Catalyst 9000 Series Switches could allow an unauthenticated,↗2025-09-24
📋Vendor Advisories
1Cisco
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