CVE-2025-12553Network attack vector

Email interception via disabled server certificate verification

Published Oct 31, 2025 · Updated Oct 31, 2025

Improper certificate validation in BLU-IC2 and BLU-IC4 through 1.19.5 allows man-in-the-middle attackers to impersonate email servers. The email client trusts an OpenSSL certificate for its configured email server without performing the required certificate-verification step. Man-in-the-middle attackers positioned between the controller and email server can present an untrusted certificate, observe or alter email traffic, and impersonate the server.

CVSS severity10.0
Critical
EPSS probability0.21%
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 BLU-IC2 and BLU-IC4 through 1.19.5 allows man-in-the-middle attackers to impersonate email servers. The email client trusts an OpenSSL certificate for its configured email server without performing the required certificate-verification step. Man-in-the-middle attackers positioned between the controller and email server can present an untrusted certificate, observe or alter email traffic, and impersonate the server.

The record

CVE
CVE-2025-12553
Published
Oct 31, 2025
Updated
Oct 31, 2025
Vendor
Azure Access Technology
Product
BLU-IC4
Classifications
CWE-599, CAPEC-94, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 31, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 31, 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 <=1.19.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Azure Access Technology · BLU-IC4version=0 <=1.19.5
Azure Access Technology · BLU-IC2version=0 <=1.19.5

Published CVSS scores

10.0Azure Access TechnologyCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA: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

CWE-599Missing Validation of OpenSSL Certificate
CAPEC-94Adversary in the Middle (AiTM)
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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