CVE-2025-20209Network attack vector

Unauthenticated control-plane UDP interruption via malformed IKEv2 packets

Published Mar 12, 2025 · Updated Mar 12, 2025

Denial of service in Cisco IOS XR Software allows remote attackers to halt control-plane UDP processing with malformed IKEv2 packets. The IKEv2 function improperly handles malformed packets and then stops processing all control-plane UDP packets. The device must be an NCS 540L, NCS 1004, NCS 1010, or NCS 1014 running an affected release with IKEv2 enabled; the condition interrupts UDP control-plane services.

CVSS severity7.5
High
EPSS probability0.54%
Next 30 days · Sep 17, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in Cisco IOS XR Software allows remote attackers to halt control-plane UDP processing with malformed IKEv2 packets. The IKEv2 function improperly handles malformed packets and then stops processing all control-plane UDP packets. The device must be an NCS 540L, NCS 1004, NCS 1010, or NCS 1014 running an affected release with IKEv2 enabled; the condition interrupts UDP control-plane services.

The record

CVE
CVE-2025-20209
Published
Mar 12, 2025
Updated
Mar 12, 2025
Vendor
ClamAV
Product
Cisco IOS XR Software
Classifications
CWE-770, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 12, 2025CVE publishedPublication date reported by the CVE source.
  2. Mar 12, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=24.1.1
  2. Affected versionversion=24.1.2
  3. Affected versionversion=24.2.1
  4. Affected versionversion=24.2.11
  5. Affected versionversion=6.5.1
  6. Affected versionversion=6.5.2
  7. Affected versionversion=6.5.3
  8. Affected versionversion=6.6.1
  9. Affected versionversion=6.6.2
  10. Affected versionversion=6.6.25
  11. Affected versionversion=6.6.3
  12. Affected versionversion=7.0.0
  13. Affected versionversion=7.0.1
  14. Affected versionversion=7.0.2
  15. Affected versionversion=7.10.1
  16. Affected versionversion=7.10.2
  17. Affected versionversion=7.1.1
  18. Affected versionversion=7.11.1
  19. Affected versionversion=7.11.2
  20. Affected versionversion=7.1.2
  21. Affected versionversion=7.2.0
  22. Affected versionversion=7.2.1
  23. Affected versionversion=7.2.2
  24. Affected versionversion=7.3.1
  25. Affected versionversion=7.3.2
  26. Affected versionversion=7.3.27
  27. Affected versionversion=7.4.1
  28. Affected versionversion=7.4.2
  29. Affected versionversion=7.5.1
  30. Affected versionversion=7.5.2
  31. Affected versionversion=7.6.1
  32. Affected versionversion=7.6.2
  33. Affected versionversion=7.7.1
  34. Affected versionversion=7.7.2
  35. Affected versionversion=7.7.21
  36. Affected versionversion=7.8.1
  37. Affected versionversion=7.8.2
  38. Affected versionversion=7.8.22
  39. Affected versionversion=7.9.1
  40. Affected versionversion=7.9.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco IOS XR Softwareversion=24.1.1; version=24.1.2; version=24.2.1; version=24.2.11; version=6.5.1; version=6.5.2; version=6.5.3; version=6.6.1; version=6.6.2; version=6.6.25; version=6.6.3; version=7.0.0; version=7.0.1; version=7.0.2; version=7.10.1; version=7.10.2; version=7.1.1; version=7.11.1; version=7.11.2; version=7.1.2; version=7.2.0; version=7.2.1; version=7.2.2; version=7.3.1; version=7.3.2; version=7.3.27; version=7.4.1; version=7.4.2; version=7.5.1; version=7.5.2; version=7.6.1; version=7.6.2; version=7.7.1; version=7.7.2; version=7.7.21; version=7.8.1; version=7.8.2; version=7.8.22; version=7.9.1; version=7.9.2

Published CVSS scores

7.5CiscoCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:X/RL:X/RC:X

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo