CVE-2025-20316

mediumpriority · track · 0EPSS 0.003 · 27 %ileDEEUNLRUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.34% (27th) EPSS
CVSS 5.3 · medium
Is it mine?
66 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A vulnerability in the access control list (ACL) programming of Cisco IOS XE Software for Cisco Catalyst 9500X and 9600X Series Switches could allow an unauthenticated, remote attacker to bypass a configured ACL on an affected device. This vulnerability is due to the flooding of traffic from an unlearned MAC address on a switch virtual interface (SVI) that has an egress ACL applied. An attacker could exploit this vulnerability by causing the VLAN to flush its MAC address table. This condition can also occur if the MAC address table is full. A successful exploit could allow the attacker to bypass an egress ACL on an affected device.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

5.3
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · FSTEC (BDU) RU
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · ENISA EU
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · psirt@cisco.com USexploitability 3.9 · impact 1.4
v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · NCSC-NL NL
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-284USCWE-284USCWE-284US
05

affected products (66)

Products and version ranges known to be affected.

showing 20 of 66
06

advisories (3)

Vendor and ecosystem advisories describing this.

  • NCSC-2025-0297Kwetsbaarheden verholpen in Cisco IOS en Cisco IOS XE SoftwareNL2025-09-25csaf · ncsc_nlNL

    Cisco heeft kwetsbaarheden verholpen in Cisco IOS en Cisco IOS XE Software.

  • WID-SEC-W-2025-2128Cisco IOS XE: Mehrere SchwachstellenDeutsch2025-09-24csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Cisco IOS XE ausnutzen, um Informationen offenzulegen, einen Denial-of-Service-Zustand zu verursachen und Sicherheitsmaßnahmen zu umgehen.

  • cisco-sa-cat9k-acl-L4K7VXgDCisco IOS XE Software on Cisco Catalyst 9500X and 9600X Series Switches Virtual Interface Access Control List Bypass Vulnerability2025-09-24csaf · cisco_csafUS

    A vulnerability in the access control list (ACL) programming of Cisco IOS XE Software for Cisco Catalyst 9500X and 9600X Series Switches could allow an unauthenticated, remote attacker to bypass a configured ACL on an affected device. This vulnerability is due to the flooding of traffic from an unlearned MAC address on a switch virtual interface (SVI) that has an egress ACL applied. An attacker could exploit this vulnerability by causing the VLAN to flush its MAC address table. This condition can also occur if the MAC address table is full. A successful exploit could allow the attacker to bypass an egress ACL on an affected device. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is part of the September 2025 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2025 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75296"].

07

also known as (5)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundcisco_csafncsc_nlNVDCVE.orgMITRE
published 2025-09-24modified 2026-06-17
09

references (4)

External citations — patches, advisories, analysis.

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