CVE-2023-4283Network attack vector

Stored XSS via unsanitized calendar shortcode

Published Aug 10, 2023 · Updated Apr 8, 2026

Stored cross-site scripting in EmbedPress 3.8.2 and earlier allows remote authenticated users to inject scripts through calendar shortcode attributes. The embedpress_calendar shortcode accepts user-supplied attributes without sufficient sanitization or output escaping, storing arbitrary script in rendered pages. Contributor-level or higher access is required, and scripts execute when another user views the injected page.

CVSS severity6.4
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 EmbedPress 3.8.2 and earlier allows remote authenticated users to inject scripts through calendar shortcode attributes. The embedpress_calendar shortcode accepts user-supplied attributes without sufficient sanitization or output escaping, storing arbitrary script in rendered pages. Contributor-level or higher access is required, and scripts execute when another user views the injected page.

The record

CVE
CVE-2023-4283
Published
Aug 10, 2023
Updated
Apr 8, 2026
Vendor
ReviewX Team
Product
EmbedPress
Classifications
CWE-79, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 10, 2023CVE 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 <=3.8.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ReviewX Team · EmbedPressversion=0 <=3.8.2

Published CVSS scores

5.4OSVCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
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.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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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