CVE-2026-3090Network attack vector

Unauthenticated stored XSS via unescaped event_type output

Published Mar 18, 2026 · Updated Mar 18, 2026

Stored XSS in WPExperts Post SMTP 3.8.0 and earlier allows remote attackers to execute scripts through crafted event_type values. PostmanEmailLogs.php renders stored event_type data into the email-log interface without sufficient output escaping, allowing browser interpretation as active script. Injection requires no authentication, but Post SMTP Pro and its Reporting and Tracking extension must be enabled and a user must open the affected log page.

CVSS severity7.2
High
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in WPExperts Post SMTP 3.8.0 and earlier allows remote attackers to execute scripts through crafted event_type values. PostmanEmailLogs.php renders stored event_type data into the email-log interface without sufficient output escaping, allowing browser interpretation as active script. Injection requires no authentication, but Post SMTP Pro and its Reporting and Tracking extension must be enabled and a user must open the affected log page.

The record

CVE
CVE-2026-3090
Published
Mar 18, 2026
Updated
Mar 18, 2026
Vendor
WPExperts
Product
Post SMTP
Classifications
CWE-79, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 18, 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=* <=3.8.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WPExperts · Post SMTPversion=* <=3.8.0

Published CVSS scores

7.2WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
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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