How to fix CVE-2025-59055?

During next maintenance window: Identify affected systems running InstantCMS and apply vendor patches when convenient. Vendor patch is available.

Is Instantcms affected by CVE-2025-59055?

Organizations using InstantCMS should be aware of moderate risk from CVE-2025-59055, a server-side request forgery vulnerability rated CVSS 4.7. Users could be tricked into performing unintended actions. Proof-of-concept code is publicly available.

CVE-2025-59055

MEDIUM

2025-09-11 [email protected]

4.7

CVSS 3.1

CVSS Vector

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

Low

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:11 vuln.today

Patch Released

Mar 28, 2026 - 19:11 nvd

Patch available

PoC Detected

Sep 24, 2025 - 13:30 vuln.today

Public exploit code

CVE Published

Sep 11, 2025 - 19:15 nvd

MEDIUM 4.7

Description

InstantCMS is a free and open source content management system. A blind Server-Side Request Forgery (SSRF) vulnerability in InstantCMS up to and including 2.17.3 allows authenticated remote attackers to make nay HTTP/HTTPS request via the package parameter. It is possible to make any HTTP/HTTPS request to any website in installer functionality. Due to such vulnerability it is possible to for example scan local network, call local services and its functions, conduct a DoS attack, and/or disclose a server's real IP if it's behind a reverse proxy. It is also possible to exhaust server resources by sending plethora of such requests. As of time of publication, no patched releases are available.

Analysis

InstantCMS is a free and open source content management system. Rated medium severity (CVSS 4.7), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.

Technical Context

This vulnerability is classified as Server-Side Request Forgery (SSRF) (CWE-918), which allows attackers to make the server perform requests to unintended internal or external resources. InstantCMS is a free and open source content management system. A blind Server-Side Request Forgery (SSRF) vulnerability in InstantCMS up to and including 2.17.3 allows authenticated remote attackers to make nay HTTP/HTTPS request via the package parameter. It is possible to make any HTTP/HTTPS request to any website in installer functionality. Due to such vulnerability it is possible to for example scan local network, call local services and its functions, conduct a DoS attack, and/or disclose a server's real IP if it's behind a reverse proxy. It is also possible to exhaust server resources by sending plethora of such requests. As of time of publication, no patched releases are available. Affected products include: Instantcms.

Affected Products

Instantcms.

Remediation

A vendor patch is available. Apply the latest security update as soon as possible. Validate and allowlist destination URLs, block requests to internal networks, use network segmentation.

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +0.2

CVSS: +24

POC: +20

CVE-2025-59055 vulnerability details – vuln.today

Back

CVE-2025-59055

CVSS Vector

Lifecycle Timeline

Tags

Description

Analysis

Technical Context

Affected Products

Remediation

Priority Score

Share

CVE-2025-59055

CVSS Vector

Lifecycle Timeline

Tags

Description

Analysis

Technical Context

Affected Products

Remediation

Priority Score

Share

External POC / Exploit Code