RCE in Dedecms
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.
Vulnerability class: RCE (Remote Code Execution)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- srcincite.io/blog/2021/09/30/chasing-a-dream-pwning-the-biggest-cms-in-china.ht… (technical-description, exploit)
- github.com/dedecms/DedeCMS/blob/v5.8.1/include/common.func.php (technical-description)
- github.com/projectdiscovery/nuclei-templates/blob/main/http/vulnerabilities/ded… (technical-description)
- www.vulncheck.com/advisories/dedecms-5.8.1-beta-unauthenticated-rce-via-plus-fl… (third-party-advisory)
Frequently asked questions
- What is CVE-2021-48016?
- CVE-2021-48016 is a critical-severity vulnerability in Dedecms, classified under Code Injection. CVSS score: 9.8/10. Published 2026-10-22.
- How severe is CVE-2021-48016?
- Critical severity. CVSS v3 base score is 9.8 out of 10.