CVE-2023-40037Network attack vector

Connection restriction bypass via noncanonical URL formatting

Published Aug 18, 2023 · Updated Feb 13, 2025

Improper input validation in Apache NiFi 1.21.0 through 1.23.0 allows remote authenticated users to bypass connection URL restrictions. The JNDI validator matched schemes without trimming evaluated values, while the JDBC validator rejected blocked schemes only at the start of a value. An authenticated user authorized to configure affected Processors or Controller Services can submit blocked connection settings; Apache specifies no further consequence.

CVSS severity6.5
Medium
EPSS probability2.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Apache NiFi 1.21.0 through 1.23.0 allows remote authenticated users to bypass connection URL restrictions. The JNDI validator matched schemes without trimming evaluated values, while the JDBC validator rejected blocked schemes only at the start of a value. An authenticated user authorized to configure affected Processors or Controller Services can submit blocked connection settings; Apache specifies no further consequence.

The record

CVE
CVE-2023-40037
Published
Aug 18, 2023
Updated
Feb 13, 2025
Vendor
The Apache Software Foundation
Product
Apache NiFi
Classifications
CWE-697, CWE-184
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record 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=1.21.0 <=1.23.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Apache Software Foundation · Apache NiFiversion=1.21.0 <=1.23.0

Published CVSS scores

6.5NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-697Incorrect Comparison
CWE-184Incomplete List of Disallowed Inputs

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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