CVE-2023-39441Network attack vector

Credential disclosure via unchecked TLS certificates

Published Aug 23, 2023 · Updated Feb 13, 2025

Improper certificate validation in Apache Airflow before 2.7.0 allows remote attackers to disclose mail credentials or contents via MITM connections. SMTP and IMAP provider clients create default OpenSSL contexts without enabling server X.509 certificate verification, so an attacker positioned between Airflow and the mail server can terminate TLS with an untrusted certificate and receive credentials or mail data. The attack requires control of the network path; the documented impact is confidentiality disclosure without integrity or availability effects.

CVSS severity5.9
Medium
EPSS probability0.80%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in Apache Airflow before 2.7.0 allows remote attackers to disclose mail credentials or contents via MITM connections. SMTP and IMAP provider clients create default OpenSSL contexts without enabling server X.509 certificate verification, so an attacker positioned between Airflow and the mail server can terminate TLS with an untrusted certificate and receive credentials or mail data. The attack requires control of the network path; the documented impact is confidentiality disclosure without integrity or availability effects.

The record

CVE
CVE-2023-39441
Published
Aug 23, 2023
Updated
Feb 13, 2025
Vendor
The Apache Software Foundation
Product
Apache Airflow IMAP Provider
Classifications
CWE-295, T1557.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 23, 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=0 <3.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Airflow IMAP Providerversion=0 <3.3.0
The Apache Software Foundation · Apache Airflowversion=0 <2.7.0
The Apache Software Foundation · Apache Airflow SMTP Providerversion=0 <1.30

Published CVSS scores

5.9NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/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 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-295Improper Certificate Validation
T1557.001Adversary-in-the-Middle

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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