CVE-2025-20209

HIGH
Published Mar 12, 2025 Modified Aug 1, 2025 CWE-770

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.

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CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-770 CWE-770

Affected Products

Vendor Product
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ios_xr
cisco ncs_1004
cisco ncs_1010
cisco ncs_1014
cisco ncs_540l

References

Frequently Asked Questions

What is 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 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. It has a CVSS v3.1 base score of 7.5 (HIGH).
How severe is CVE-2025-20209? +
CVE-2025-20209 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
What products are affected by CVE-2025-20209? +
CVE-2025-20209 affects products from cisco, specifically: ios_xr, ncs_1004, ncs_1010, ncs_1014, ncs_540l. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-20209? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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