High severity · published Mar 12, 2025
CVE-2025-20209
A vulnerability in the Internet Key Exchange version 2 (IKEv2) function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent an affected device from…
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
A vulnerability in the Internet Key Exchange version 2 (IKEv2) function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent an affected device from processing any control plane UDP packets.
This vulnerability is due to improper handling of malformed IKEv2 packets. An attacker could exploit this vulnerability by sending malformed IKEv2 packets to an affected device. A successful exploit could allow the attacker to prevent the affected device from processing any control plane UDP packets, resulting in a denial of service (DoS) condition.
Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IX
Ios XR · Cisco
6.5.1; 6.5.2; 6.5.3; 6.6.1; 6.6.2; 6.6.3; +34 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-20209
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-20209
Not Applicable
https://blog.apnic.net/2024/09/02/crafting-endless-as-paths-in-bgp/
Vendor Advisory
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xrike-9wYGpRGq
More from Ios XR
8.8
CVE-2020-3118
Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability
8.8
CVE-2018-0167
Cisco IOS, XR, and XE Software Buffer Overflow Vulnerability
8.6
CVE-2020-3569
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
8.6
CVE-2020-3566
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
8.0
CVE-2018-0175
Cisco IOS, XR, and XE Software Buffer Overflow Vulnerability