CVE-2026-78374Network attack vector

Unauthenticated email relay via request-controlled recipients

Published Sep 10, 2026 · Updated Sep 10, 2026

Improper recipient validation in JoomlArt T4 Page Builder before 2.3.0 allows remote attackers to relay arbitrary email through a Joomla site. The front-end contact action trusts a request-supplied recipient, subject, and HTML body, then sends the message under the site's configured sender identity. No authentication is required; without configured Captcha, repeated submissions can send attacker-chosen messages to arbitrary recipients without rate limits.

CVSS severityUnavailable
Unscored
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper recipient validation in JoomlArt T4 Page Builder before 2.3.0 allows remote attackers to relay arbitrary email through a Joomla site. The front-end contact action trusts a request-supplied recipient, subject, and HTML body, then sends the message under the site's configured sender identity. No authentication is required; without configured Captcha, repeated submissions can send attacker-chosen messages to arbitrary recipients without rate limits.

The record

CVE
CVE-2026-78374
Published
Sep 10, 2026
Updated
Sep 10, 2026
Vendor
JoomlArt
Product
T4 Page Builder
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 10, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.0-2.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

JoomlArt · T4 Page Builderversion=1.0.0-2.2.0

Published CVSS scores

No CVSS assessment is available in this record.

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.

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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

T1190Exploit Public-Facing Application

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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