PT-2025-20263 · Cisco · Cisco Ios+5
CVE-2025-20191
·
Published
2025-05-07
·
Updated
2026-05-23
CVSS v3.1
7.4
High
| Vector | AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
Name of the Vulnerable Software and Affected Versions
Cisco IOS Software (affected versions not specified)
Cisco IOS XE Software (affected versions not specified)
Cisco NX-OS Software (affected versions not specified)
Cisco Wireless LAN Controller (WLC) AireOS Software (affected versions not specified)
Description
A vulnerability in the Switch Integrated Security Features (SISF) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This issue is due to the incorrect handling of DHCPv6 packets. An attacker could exploit this by sending a crafted DHCPv6 packet to an affected device, potentially causing the device to reload and resulting in a DoS condition.
Recommendations
For Cisco IOS Software, update to a version that includes the fix for this issue.
For Cisco IOS XE Software, update to a version that includes the fix for this issue.
For Cisco NX-OS Software, update to a version that includes the fix for this issue.
For Cisco Wireless LAN Controller (WLC) AireOS Software, update to a version that includes the fix for this issue.
As a temporary workaround, consider restricting access to DHCPv6 packets to minimize the risk of exploitation.
Fix
DoS
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Weakness Enumeration
Related Identifiers
Affected Products
Cisco Ios
Cisco Ios Xe
Cisco Nx-Os
Cisco Nexus
Cisco Wireless Lan Controller (Wlc) Aireos
Cisco Wls