CVE-2026-17089Network attack vector

Reflected XSS via unsanitized grouped-event header

Published Aug 25, 2026 · Updated Aug 25, 2026

Reflected XSS in Marcus Sykes Events Manager 7.4.0.1 and earlier allows remote attackers to run scripts through a crafted link. The unauthenticated search_events_grouped AJAX action skips the shortcode path's wp_kses() sanitization, and output_grouped() echoes header_format into the HTML body. A victim must open the attacker-controlled link; the resulting script runs in that victim's browser context.

CVSS severity6.1
Medium
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Marcus Sykes Events Manager 7.4.0.1 and earlier allows remote attackers to run scripts through a crafted link. The unauthenticated search_events_grouped AJAX action skips the shortcode path's wp_kses() sanitization, and output_grouped() echoes header_format into the HTML body. A victim must open the attacker-controlled link; the resulting script runs in that victim's browser context.

The record

CVE
CVE-2026-17089
Published
Aug 25, 2026
Updated
Aug 25, 2026
Vendor
Marcus Sykes
Product
Events Manager
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 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 <=7.4.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Marcus Sykes · Events Managerversion=0 <=7.4.0.1

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')
T1203Exploitation for Client Execution

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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