---
id: CVE-2021-48016
title: DedeCMS 5.8.1-beta Unauthenticated RCE via plus/flink.php
summary: >-
  DedeCMS through 5.8.1-beta contains a PHP code injection vulnerability in
  ShowMsg() where the HTTP Referer header is written into a DedeTemplate string
  and included. Unauthenticated attackers can send a crafted Referer to
  /plus/flink.php…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-94
vendor: DedeCMS
product: DedeCMS
affected:
  - DedeCMS <= 5.8.1-beta
published: '2026-10-22'
updated: '2026-10-22'
sourceUpdated: '2026-10-22T10:57:31.176Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2021-48016'
references:
  - url: >-
      https://srcincite.io/blog/2021/09/30/chasing-a-dream-pwning-the-biggest-cms-in-china.html
    label: Source Incite Blog
  - url: 'https://github.com/dedecms/DedeCMS/blob/v5.8.1/include/common.func.php'
    label: DedeCMS v5.8.1 common.func.php ShowMsg
  - url: >-
      https://github.com/projectdiscovery/nuclei-templates/blob/main/http/vulnerabilities/dedecms/dedecms-rce.yaml
    label: Nuclei Template
  - url: >-
      https://www.vulncheck.com/advisories/dedecms-5.8.1-beta-unauthenticated-rce-via-plus-flink-php
    label: >-
      VulnCheck Advisory: DedeCMS 5.8.1-beta Unauthenticated RCE via
      plus/flink.php
tags:
  - cve.org
ingestedAt: '2026-10-22T11:37:02.342Z'
---

## Overview

DedeCMS through 5.8.1-beta contains a PHP code injection vulnerability in ShowMsg() where the HTTP Referer header is written into a DedeTemplate string and included. Unauthenticated attackers can send a crafted Referer to /plus/flink.php?dopost=save with an empty validate code to execute arbitrary PHP and system commands. Exploitation evidence was first observed by the Shadowserver Foundation on 2023-10-14.

## Affected

- `DedeCMS <= 5.8.1-beta`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.