CVE-2026-48707: CWE-918: Server-Side Request Forgery (SSRF) in instantsoft icms2
Description
InstantCMS is a free and open source content management system. Versions prior to 2.18.2 have a Server-Side Request Forgery (SSRF) vulnerability in the file upload functionality (`system/core/uploader.php` at lines 509-532). When the "upload from URL" feature follows an HTTP redirect, the redirected target URL bypasses the private IP address blacklist check. This allows authenticated users to scan and access internal network services. Version 2.18.2 contains a fix.
CVSS v3.1
Score 3.1low
Affected software
instantsoft
icms2
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
InstantCMS (icms2) before version 2.18.2 contains an SSRF vulnerability in the file upload component (system/core/uploader.php, lines 509-532). Specifically, when using the "upload from URL" feature, HTTP redirects are followed without properly enforcing the private IP address blacklist on the redirected target URL. This flaw allows authenticated users to perform SSRF attacks that can scan or access internal network services. Version 2.18.2 addresses this vulnerability with a fix.
Potential Impact
The vulnerability allows authenticated users to bypass internal network restrictions by exploiting SSRF via the upload from URL feature. This can lead to unauthorized scanning and access of internal network services. The CVSS score is 3.1 (low severity), indicating limited impact primarily on confidentiality with no direct impact on integrity or availability.
Mitigation Recommendations
Upgrade InstantCMS to version 2.18.2 or later, where the SSRF vulnerability has been fixed. No additional mitigation is required if the system is updated. Patch status is confirmed by the vendor's fix in version 2.18.2.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-22T18:47:27.755Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aa047f9acd9273b49ff656b
Added to database: 09/08/2026, 17:38:01 UTC
Last enriched: 09/16/2026, 01:20:57 UTC
Last updated: 10/23/2026, 01:15:24 UTC
Views: 118
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