- 7.4HighCVSS base score
- 0.24%Exploitation in 30 daysEPSS · top 84% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By cisco
- 7 months later
· 7 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.1 | High7.4 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Deferred | 3.1 | High7.4 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.24% · top 84% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.4.
Affected products
- affected 8.2(5)
- affected 7.3(5)D1(1)
- affected 8.4(2)
- affected 8.4(3)
- affected 9.2(3)
- affected 9.2(2v)
- affected 7.3(4)D1(1)
- affected 8.2(1)
- affected 9.2(1)
- affected 9.2(2t)
- affected 9.2(3y)
- affected 7.0(3)I7(6z)
- affected 9.3(2)
- affected 7.0(3)I7(3z)
- affected 7.0(3)IM7(2)
- affected 7.0(3)I7(5a)
- affected 8.1(1)
- affected 8.2(2)
- affected 8.3(2)
- affected 7.3(2)D1(3a)
- affected 9.2(4)
- affected 8.1(2)
- affected 7.3(3)D1(1)
- affected 8.2(3)
- affected 7.0(3)I7(2)
- affected 7.0(3)I7(3)
- affected 8.4(1)
- affected 7.3(0)DX(1)
- affected 7.3(2)D1(1)
- affected 9.3(1)
- affected 7.0(3)I7(6)
- affected 7.3(2)D1(2)
- affected 8.2(4)
- affected 7.0(3)I7(4)
- affected 7.0(3)I7(7)
- affected 9.3(1z)
- affected 9.2(2)
- affected 8.1(2a)
- affected 7.3(2)D1(3)
- affected 7.0(3)I7(5)
- and 79 more
Cisco · Cisco Wireless LAN Controller (WLC)
- affected 8.10.112.0
- affected 8.8.120.0
- affected 8.3.143.0
- affected 8.3.111.0
- affected 8.2.164.0
- affected 8.5.109.0
- affected 8.3.132.0
- affected 8.5.105.0
- affected 8.2.170.0
- affected 8.2.160.0
- affected 8.8.100.0
- affected 8.9.111.0
- affected 8.7.102.0
- affected 8.3.102.0
- affected 8.3.133.0
- affected 8.3.131.0
- affected 8.5.100.0
- affected 8.5.131.0
- affected 8.3.122.0
- affected 8.5.101.0
- affected 8.3.112.0
- affected 8.5.120.0
- affected 8.2.141.0
- affected 8.3.141.0
- affected 8.3.121.0
- affected 8.2.151.0
- affected 8.3.130.0
- affected 8.5.102.0
- affected 8.2.161.0
- affected 8.5.151.0
- affected 8.2.100.0
- affected 8.5.135.0
- affected 8.3.135.0
- affected 8.5.140.0
- affected 8.7.106.0
- affected 8.9.100.0
- affected 8.8.111.0
- affected 8.2.110.0
- affected 8.5.110.0
- affected 8.2.130.0
- and 44 more
What to do
Exploitation: The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-13915 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-20191)Record last updated .