cbcvebase.
CVE-2018-10823
published 2018-10-17

CVE-2018-10823: An issue was discovered on D-Link DWR-116 through 1.06, DWR-512 through 2.02, DWR-712 through 2.02, DWR-912 through 2.02, DWR-921 through 2.02, and DWR-111…

PriorityP186high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
78.19%
99.5th percentile
An issue was discovered on D-Link DWR-116 through 1.06, DWR-512 through 2.02, DWR-712 through 2.02, DWR-912 through 2.02, DWR-921 through 2.02, and DWR-111 through 1.01 devices. An authenticated attacker may execute arbitrary code by injecting the shell command into the chkisg.htm page Sip parameter. This allows for full control over the device internals.

Affected

4 ranges
VendorProductVersion rangeFixed in
dlinkdwr-111_firmware<= 1.01
dlinkdwr-116_firmware<= 1.06
dlinkdwr-512_firmware<= 2.02
dlinkdwr-912_firmware<= 2.02

Detection & IOCsextracted from sources · hover to see the quote

url/chkisg.htm%3FSip%3D1.1.1.1%20%7C%20cat%20%2Fetc%2Fpasswd
path/chkisg.htm
snort
alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (msg:"ET EXPLOIT D-Link DWR Command Injection Inbound (CVE-2018-10823)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/chkisg.htm"; content:"%3FSip%"; fast_pattern; nocase; distance:0; content:"%7C"; nocase; distance:0; reference:cve,2018-10823; classtype:attempted-admin; sid:2035953; rev:2; metadata:attack_target Networking_Equipment, created_at 2022_04_14, cve CVE_2018_10823, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, updated_at 2024_03_08, mitre_tactic_id TA0008, mitre_tactic_name Lateral_Movement, mitre_technique_id T1210, mitre_technique_name Exploitation_Of_Remote_Services;)
  • Exploit requests use HTTP GET to /chkisg.htm with a URL-encoded Sip parameter containing a pipe character (%7C) for command injection. Look for GET requests where the URI contains both '/chkisg.htm' and '%7C' (pipe).
  • Successful exploitation response will contain the contents of /etc/passwd, detectable by the regex pattern 'root:.*:0:0:' in the HTTP response body.
  • The attack requires prior authentication to the router. Monitor for authenticated sessions followed immediately by requests to /chkisg.htm with encoded shell metacharacters in the Sip parameter.
  • The Emergingthreats rule (SID 2035953) targets inbound traffic to $HOME_NET/$HTTP_SERVERS, classifying the attack as attempted-admin with high confidence, mapped to MITRE T1210 (Exploitation of Remote Services).
  • ·Exploitation requires the attacker to be authenticated to the router first. Unauthenticated access alone is insufficient to trigger the command injection.
  • ·The vulnerability likely affects additional D-Link models beyond those explicitly listed, if they share the same firmware type.

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.09.0CRITICALAV:N/AC:L/Au:S/C:C/I:C/A:C
vulncheck8.8HIGH
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