CVE-2026-27437Network attack vector

Unauthenticated object injection via unsafe skin deserialization

Published Mar 5, 2026 · Updated Mar 5, 2026

PHP object injection in ThemeREX Tennis Club 1.2.3 and earlier allows remote attackers to instantiate objects through serialized input. The theme unserializes scheme_storage and skin-option data without adequate validation during skin installation or activation. No authentication or user interaction is required, while code execution and other follow-on effects require a usable PHP object-population chain.

CVSS severity9.8
Critical
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

PHP object injection in ThemeREX Tennis Club 1.2.3 and earlier allows remote attackers to instantiate objects through serialized input. The theme unserializes scheme_storage and skin-option data without adequate validation during skin installation or activation. No authentication or user interaction is required, while code execution and other follow-on effects require a usable PHP object-population chain.

The record

CVE
CVE-2026-27437
Published
Mar 5, 2026
Updated
Mar 5, 2026
Vendor
ThemeREX
Product
Tennis Club
Classifications
CWE-502, CAPEC-586, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 5, 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=n/a <=<= 1.2.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ThemeREX · Tennis Clubversion=n/a <=<= 1.2.3

Published CVSS scores

9.8PatchstackCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CAPEC-586Object Injection
T1190Exploit Public-Facing Application

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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