CVE-2023-5958Public exploitNetwork attack vector

Stored XSS via unescaped email log content

Published Nov 27, 2023 · Updated Aug 2, 2024

Stored cross-site scripting in WPExperts Post SMTP before 2.7.1 allows remote attackers to execute scripts through crafted email content. The email logger stores message bodies supplied through wp_mail and renders them in the administrative email-log view without escaping their HTML content. No authentication is required to submit the message through a public contact form, but a highly privileged user must open its log entry; execution is limited to that user's browser context.

CVSS severity6.1
Medium
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in WPExperts Post SMTP before 2.7.1 allows remote attackers to execute scripts through crafted email content. The email logger stores message bodies supplied through wp_mail and renders them in the administrative email-log view without escaping their HTML content. No authentication is required to submit the message through a public contact form, but a highly privileged user must open its log entry; execution is limited to that user's browser context.

The record

CVE
CVE-2023-5958
Published
Nov 27, 2023
Updated
Aug 2, 2024
Vendor
WPExperts
Product
Post SMTP
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record 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 <2.7.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WPExperts · Post SMTPversion=0 <2.7.1

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/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 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 exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

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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