Server-Side Request Forgery Vulnerability in Poesis Rhymix CMS by Poesis Inc.
CVE-2026-18856

5.1MEDIUM

Key Information:

Vendor

Poesis

Status
Rhymix Cms
Vendor
CVE Published:
5 August 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-18856?

A security flaw has been identified in Poesis Rhymix CMS in versions up to 2.1.33, specifically in the procImporterAdminCheckXmlFile function found in the Data Import Module. This vulnerability makes the system susceptible to server-side request forgery (SSRF), potentially allowing remote attackers to manipulate file arguments and execute unauthorized requests. It is crucial for users to upgrade to version 2.1.34 to mitigate this issue and protect their installations promptly.

Affected Version(s)

Rhymix CMS 2.1.0

Rhymix CMS 2.1.1

Rhymix CMS 2.1.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-18856 - Proof of Concept

References

https://vuldb.com/vuln/385868
vdb-entrytechnical-description
https://vuldb.com/vuln/385868/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-18856
third-party-advisory

CVSS V4

Score:
5.1
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

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