CVE-2021-48016 (GCVE-0-2021-48016)

Vulnerability from cvelistv5 – Published: 2026-10-22 10:57 – Updated: 2026-10-22 10:57 X_Known Exploited Vulnerability Unsupported When Assigned
VLAI Previdian
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?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.
Severity
9.3 (Critical)
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
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6753 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
DedeCMS DedeCMS Affected: 0 , ≤ 5.8.1-beta (custom)
    cpe:2.3:a:dedecms:dedecms:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2021-09-30 00:00
Credits
The Shadowserver Foundation
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: d69cc72d-6fcf-4968-8ce5-eb8c6fb51757

Vulnerability ID: CVE-2021-48016

Status: Confirmed

Status Updated: 2026-10-22 11:10 UTC

Exploited: Yes

Timestamps
First Seen: 2026-10-22
Asserted: 2026-10-22
Scope
Notes: DedeCMS 5.8.1-beta Unauthenticated RCE via plus/flink.php | Affected: DedeCMS / DedeCMS | CVSS: 9.3 (CRITICAL) | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: previdian

Details
Feed Previdian (previdian.com)
Title DedeCMS 5.8.1-beta Unauthenticated RCE via plus/flink.php
Cve Id CVE-2021-48016
Vendor DedeCMS
Ghsa Id None
Product DedeCMS
Added Date 2026-10-22T11:10:53.398Z
Cvss Score 9.3
Epss Score None
Previous Ids
Cvss Severity CRITICAL
Virtual Patch False
Cvss Estimated False
Epss Percentile None
Used In Malware unknown
Vulnerability Id CVE-2021-48016
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-10-23 12:00 UTC | Updated: 2026-10-23 12:00 UTC
Show details on NVD website
To clipboard 

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