CVE-2023-39340Network attack vector

Unauthenticated appliance denial of service via crafted request

Published Dec 16, 2023 · Updated Nov 27, 2024

Denial of service in Ivanti Connect Secure before 22.6R2 allows remote attackers to interrupt the appliance via a crafted request. Ivanti has not disclosed the request path, parser, or faulty operation that causes the appliance to fail. No authentication or user interaction is required, and the published impact is limited to availability; public records do not distinguish a crash, hang, or reboot.

CVSS severity7.5
High
EPSS probability2.38%
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 Ivanti Connect Secure before 22.6R2 allows remote attackers to interrupt the appliance via a crafted request. Ivanti has not disclosed the request path, parser, or faulty operation that causes the appliance to fail. No authentication or user interaction is required, and the published impact is limited to availability; public records do not distinguish a crash, hang, or reboot.

The record

CVE
CVE-2023-39340
Published
Dec 16, 2023
Updated
Nov 27, 2024
Vendor
Ivanti
Product
Connect Secure
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 16, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 27, 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=22.6.1 <22.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ivanti · Connect Secureversion=22.6.1 <22.6.1

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5HackerOneCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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

T1499.004Endpoint Denial of Service: Application 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

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Your stack

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