Vulnerability details

CVE-2021-48016

dedecms DedeCMS

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

CVSS 4.0

9.3Critical

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.

CVSS scores

Score	Version	Source	Vector
9.3Critical	4.0	CVEProject cvelistV5 (CNA) (VulnCheck)	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`
9.8Critical	3.1	CVEProject cvelistV5 (CNA) (VulnCheck)	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

Affected products

Vendor	Product	Versions	Source
dedecms	DedeCMS	v ≤ 5.8.1-beta	CVEProject cvelistV5 (CNA)

References and advisories

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

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Details

Published: 2026-10-22
Last updated: 2026-10-29
State: Published
Assigner (CNA): VulnCheck

Exploit prediction (EPSS)

0.44%

Probability of exploitation in 30 days

38.5%

Percentile (among all CVEs)

SSVC assessment (CISA)

Automatable: Yes
Exploitation: Proof of concept
Technical impact: Total

Weaknesses (CWE)

CWE-94
Improper Control of Generation of Code ('Code Injection')