CVE-2025-20191
Multiple Cisco Products Denial of Service Vulnerability
Reported by cisco · Published May 7, 2025
A vulnerability in the Switch Integrated Security Features (SISF) of Cisco IOS Software, Cisco IOS XE Software, Cisco NX-OS Software, and Cisco Wireless LAN Controller (WLC) AireOS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to the incorrect handling of DHCPv6 packets. An attacker could exploit this vulnerability by sending a crafted DHCPv6 packet to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Risk scores
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco NX-OS Software | 8.2(5), 7.3(5)D1(1), 8.4(2) |
| Cisco | Cisco Wireless LAN Controller (WLC) | 8.10.112.0, 8.8.120.0, 8.3.143.0 |
| Cisco | Cisco Wireless LAN Controller (WLC) | 8.10.112.0, 8.8.120.0, 8.3.143.0 |
| Cisco | Cisco NX-OS Software | 8.2(5), 7.3(5)D1(1), 8.4(3) |
Timeline
- May 7, 2025 CVE Published
- May 7, 2025 CVE Updated
- May 8, 2025 EPSS Score (30 in total, the first dated here)
- Jun 17, 2025 Coalition ESS Score (9 in total, the first dated here)
- Apr 1, 2026 Security Advisory
Query this with the API
The same record, from the CLI:
vulnetix vdb vuln CVE-2025-20191
vulnetix vdb fixes CVE-2025-20191Or with curl, using the org id and key from your account page:
curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
"https://api.vdb.vulnetix.com/v2/vuln/CVE-2025-20191/fixes/registry"The Community plan is free and allows 50 queries a day. Get a free API key · API quickstart