CVE-2025-5807Network attack vector

Stored XSS via unsanitized BBcode content

Published Jul 10, 2025 · Updated Apr 8, 2026

Stored XSS in Marcel Pol Gwolle Guestbook 4.9.2 and earlier allows remote attackers to run scripts through guestbook content. The BBcode formatter accepts gwolle_gb_content and emits URL and image markup without applying esc_url and wp_kses to embedded data. An unauthenticated visitor can store the payload, but execution requires another user to view the published entry, exposing data or actions available in that user's browser session.

CVSS severity6.1
Medium
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

Stored XSS in Marcel Pol Gwolle Guestbook 4.9.2 and earlier allows remote attackers to run scripts through guestbook content. The BBcode formatter accepts gwolle_gb_content and emits URL and image markup without applying esc_url and wp_kses to embedded data. An unauthenticated visitor can store the payload, but execution requires another user to view the published entry, exposing data or actions available in that user's browser session.

The record

CVE
CVE-2025-5807
Published
Jul 10, 2025
Updated
Apr 8, 2026
Vendor
Marcel Pol
Product
Gwolle Guestbook
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 10, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 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=0 <=4.9.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Marcel Pol · Gwolle Guestbookversion=0 <=4.9.2

Published CVSS scores

6.1WordfenceCVSS: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 exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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