TI-2026-06135 Aliases CVE-2026-7011 GHSA-2p3h-3pf2-9rg6

MaxSite CMS Antispam Plugin plugin_antispam cross site scripting

MEDIUM 55CWE-79Published 2026-04-26 · Updated 2026-04-27

Key facts

Attack vector: Network
Privileges required: High
User interaction: Passive
Attack complexity: Low
Attack requirements: None
Impact type: Cross-site scripting, Code execution
Confidentiality · integrity · availability: None · Low · None
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79 and CWE-94.

Summary

A weakness has been identified in MaxSite CMS up to 109.3. Affected by this vulnerability is an unknown functionality of the file /admin/plugin_antispam of the component Antispam Plugin. Executing a manipulation of the argument f_logging_file can lead to cross site scripting. It is possible to launch the attack remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 109.4 addresses this issue. This patch is called 8a3946bd0a54bfb72a4d57179fcd253f2c550cd7. Upgrading the affected component is advised. The vendor was informed early about this issue. They classify it as a "Self-XSS". They deployed a countermeasure: "Nevertheless, we consider this a violation of secure coding standards. The lack of filtering via `htmlspecialchars()` has already been fixed in the latest patch to prevent incorrect data display."

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00269 19th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by the CNA

Fix Fixed CMS (MaxSite): 109.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
MaxSite	CMS	109.0; 109.1; 109.2; 109.3	109.4	Patch available	CNA

CMS VendorMaxSite Affected 109.0; 109.1; 109.2; 109.3 Fixed in 109.4 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:max-3000:maxsite_cms::::::::	—	—	Max-3000

cpe:2.3:a:max-3000:maxsite_cms:*:*:*:*:*:*:*:* Versions — — ·Max-3000

Remediation

Fix · CNA CMS (MaxSite) Fixed in 109.4

Timeline

2026-10-02 Threatist record created from CVE-2026-7011
2026-10-03 Alias added: GHSA-2p3h-3pf2-9rg6

References

Exploit 1

https://github.com/wnaspy/CVE/blob/main/Report-%20Stored%20XSS-in-antispam-plugin-maxsite-cms.pdf

Patch 2

Other 1

https://github.com/maxsite/cms/

TI-2026-59994 MaxSite CMS through 109.6 Authentication Bypass via Hardcoded Encryption Key CVSS 4.0CRITICAL 9.3
TI-2026-59992 MaxSite CMS through 109.6 Local File Inclusion via ajax dispatcher CVSS 4.0HIGH 8.8
TI-2026-59995 MaxSite CMS through 109.6 PHP Object Injection via ci_session CVSS 4.0CRITICAL 9.2
TI-2026-02931 MaxSite CMS MarkItUp Preview AJAX Endpoint preview-ajax.php eval code injection CVSS 4.0MEDIUM 6.9
TI-2025-11324 MaxSite CMS save-file-ajax.php unrestricted upload CVSS 4.0MEDIUM 5.3
TI-2026-06140 MaxSite CMS ushki Plugin cross site scripting CVSS 4.0MEDIUM 4.8

See all 18 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences