CVE-2021-48016

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/dedecms/DedeCMS/blob/v5.8.1/include/common.func.php
https://github.com/projectdiscovery/nuclei-templates/blob/main/http/vulnerabilities/dedecms/dedecms-rce.yaml
https://srcincite.io/blog/2021/09/30/chasing-a-dream-pwning-the-biggest-cms-in-china.html
https://www.vulncheck.com/advisories/dedecms-5.8.1-beta-unauthenticated-rce-via-plus-flink-php

Configurations

No configuration.

History

22 Oct 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 11:17

Updated : 2026-10-29 04:18

NVD link : CVE-2021-48016

Mitre link : CVE-2021-48016

CVE.ORG link : CVE-2021-48016

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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