CVE-2020-3230Network attack vector

IKEv2 service interruption via SA-Init queue exhaustion

Published Jun 3, 2020 · Updated Nov 15, 2024

Denial of service in Cisco IOS with IKEv2 configured allows remote attackers to prevent establishment of new security associations. Crafted SA-Init packets are handled incorrectly and consume the maximum incoming-negotiation slots, blocking subsequent IKEv2 negotiations. The device must process IKEv2 traffic on a supported UDP port; a saturated queue can persist until the device is power-cycled.

CVSS severity7.5
High
EPSS probability1.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Cisco IOS with IKEv2 configured allows remote attackers to prevent establishment of new security associations. Crafted SA-Init packets are handled incorrectly and consume the maximum incoming-negotiation slots, blocking subsequent IKEv2 negotiations. The device must process IKEv2 traffic on a supported UDP port; a saturated queue can persist until the device is power-cycled.

The record

CVE
CVE-2020-3230
Published
Jun 3, 2020
Updated
Nov 15, 2024
Vendor
Cisco
Product
Cisco IOS
Classifications
CWE-20, T1499.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 3, 2020CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Cisco · Cisco IOSversion=n/a

Published CVSS scores

7.5CiscoCVSS:3.0/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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.002Service Exhaustion Flood

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

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Your stack

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