CVE-2026-44393Network attack vector

Man-in-the-middle interception via omitted TLS hostname check

Published Jun 4, 2026 · Updated Jun 4, 2026

Improper TLS hostname validation in OpenStack oslo.messaging 1.0.0 through 17.3.0 allows man-in-the-middle attackers to intercept RPC traffic. The RabbitMQ driver validates the broker certificate chain when ssl_ca_file is set but omits the expected broker hostname from the underlying TLS check. Exposure is limited to TLS-enabled RabbitMQ deployments; exploitation requires control-plane network access and a certificate trusted by the deployment CA.

CVSS severity7.4
High
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper TLS hostname validation in OpenStack oslo.messaging 1.0.0 through 17.3.0 allows man-in-the-middle attackers to intercept RPC traffic. The RabbitMQ driver validates the broker certificate chain when ssl_ca_file is set but omits the expected broker hostname from the underlying TLS check. Exposure is limited to TLS-enabled RabbitMQ deployments; exploitation requires control-plane network access and a certificate trusted by the deployment CA.

The record

CVE
CVE-2026-44393
Published
Jun 4, 2026
Updated
Jun 4, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-295, CWE-297, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.4GitLab Advisory DatabaseCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
CWE-297Improper Validation of Certificate with Host Mismatch
T1557Adversary-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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