CVE-2025-13856Network attack vector

Stored script execution via unescaped shortcode ID

Published Dec 6, 2025 · Updated Apr 8, 2026

Stored XSS in Extra Post Images 1.0 and earlier allows remote authenticated users to inject scripts through the extra-images shortcode. The shortcode handler places the attacker-controlled id attribute into generated page markup without sanitizing the value or escaping it for HTML output. Contributor-level access is required to save the payload, which executes in a visitor's browser whenever the affected page is viewed.

CVSS severity6.4
Medium
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 Extra Post Images 1.0 and earlier allows remote authenticated users to inject scripts through the extra-images shortcode. The shortcode handler places the attacker-controlled id attribute into generated page markup without sanitizing the value or escaping it for HTML output. Contributor-level access is required to save the payload, which executes in a visitor's browser whenever the affected page is viewed.

The record

CVE
CVE-2025-13856
Published
Dec 6, 2025
Updated
Apr 8, 2026
Vendor
michaelcole1991
Product
Extra Post Images
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 6, 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 <=1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

michaelcole1991 · Extra Post Imagesversion=0 <=1.0

Published CVSS scores

6.4WordfenceCVSS:3.1/AV:N/AC:L/PR:L/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.

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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
Privilegesauthenticated
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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