Vulnerability · Published Oct 22, 2026 · Assigned by VulnCheck

CVE-2021-48016DedeCMS 5.8.1-beta Unauthenticated RCE via plus/flink.php

Critical 9.8

In plain English

A critical-severity code injection in DedeCMS from DedeCMS. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)0.4%top 61.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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 products (as reported)

Vendor	Product	Versions
DedeCMS	DedeCMS	0 – through 5.8.1-beta

Weakness: CWE-94 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Source Incite Blog technical-description, exploit
DedeCMS v5.8.1 common.func.php ShowMsg technical-description
Nuclei Template technical-description
VulnCheck Advisory: DedeCMS 5.8.1-beta Unauthenticated RCE via plus/flink.php third-party-advisory