CVE-2026-33386: CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') in OpenSolution QuickCMS
QuickCMS is vulnerable to Cross-Site Scripting (XSS) through its insecure HTTP-based plugin‑fetching mechanism. A malicious attacker can perform a Man‑in‑the‑Middle (MITM) attack by impersonating the opensolution.org server and serving arbitrary HTML or JavaScript at the plugin list endpoint. When a user accesses the plugin page, the malicious content is automatically fetched, rendered, and executed. This issue was fixed in a patch to version 6.8 published on 15.05.2026, deployments without this patch are still vulnerable.
AI Analysis
Technical Summary
CVE-2026-33386 describes an XSS vulnerability in OpenSolution QuickCMS caused by insecure HTTP fetching of plugin data. This allows an attacker to conduct a MITM attack to inject arbitrary HTML or JavaScript by impersonating the plugin server. When the plugin page is accessed, the malicious content is rendered and executed in the user's browser. The issue was addressed in QuickCMS version 6.8 with a patch released on 2026-05-15. No cloud service is involved, and no known exploits are reported in the wild.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary scripts in the context of the affected QuickCMS plugin page, potentially leading to session hijacking or other client-side attacks. However, the CVSS score of 2.3 indicates the impact is low, reflecting limited attack vector and conditions. The vulnerability requires a MITM position and no user interaction is needed, but privileges or sensitive data exposure is not indicated.
Mitigation Recommendations
A patch fixing this vulnerability was released in QuickCMS version 6.8 on 2026-05-15. Users should upgrade to version 6.8 or later to remediate this issue. Since no official remediation level or vendor advisory link is provided, verify the patch availability from OpenSolution's official sources. Deployments not updated remain vulnerable. No additional mitigations are specified.
CVE-2026-33386: CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') in OpenSolution QuickCMS
Description
QuickCMS is vulnerable to Cross-Site Scripting (XSS) through its insecure HTTP-based plugin‑fetching mechanism. A malicious attacker can perform a Man‑in‑the‑Middle (MITM) attack by impersonating the opensolution.org server and serving arbitrary HTML or JavaScript at the plugin list endpoint. When a user accesses the plugin page, the malicious content is automatically fetched, rendered, and executed. This issue was fixed in a patch to version 6.8 published on 15.05.2026, deployments without this patch are still vulnerable.
CVSS v4.0
Score 2.3low
Affected software
pkg:github/opensolution/quickcmsRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-33386 describes an XSS vulnerability in OpenSolution QuickCMS caused by insecure HTTP fetching of plugin data. This allows an attacker to conduct a MITM attack to inject arbitrary HTML or JavaScript by impersonating the plugin server. When the plugin page is accessed, the malicious content is rendered and executed in the user's browser. The issue was addressed in QuickCMS version 6.8 with a patch released on 2026-05-15. No cloud service is involved, and no known exploits are reported in the wild.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary scripts in the context of the affected QuickCMS plugin page, potentially leading to session hijacking or other client-side attacks. However, the CVSS score of 2.3 indicates the impact is low, reflecting limited attack vector and conditions. The vulnerability requires a MITM position and no user interaction is needed, but privileges or sensitive data exposure is not indicated.
Mitigation Recommendations
A patch fixing this vulnerability was released in QuickCMS version 6.8 on 2026-05-15. Users should upgrade to version 6.8 or later to remediate this issue. Since no official remediation level or vendor advisory link is provided, verify the patch availability from OpenSolution's official sources. Deployments not updated remain vulnerable. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- CERT-PL
- Date Reserved
- 2026-03-19T10:45:47.736Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a19bc63e29bf47b50f702e0
Added to database: 05/29/2026, 16:18:43 UTC
Last enriched: 05/29/2026, 16:34:37 UTC
Last updated: 07/25/2026, 20:52:04 UTC
Views: 58
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