cbcvebase.
CVE-2022-26187
published 2022-03-22

CVE-2022-26187: TOTOLINK N600R V4.3.0cu.7570_B20200620 was discovered to contain a command injection vulnerability via the pingCheck function.

PriorityP187critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWVulnCheck KEV
Exploited in the wild
EPSS
19.58%
97.0th percentile
TOTOLINK N600R V4.3.0cu.7570_B20200620 was discovered to contain a command injection vulnerability via the pingCheck function.

Affected

1 ranges
VendorProductVersion rangeFixed in
totolinkn600r_firmware

Detection & IOCsextracted from sources · hover to see the quote

path/cgi-bin/cstecgi.cgi
snort
alert http any any -> $HOME_NET any (msg:"ET WEB_SPECIFIC_APPS TOTOLINK N600R cstecgi.cgi ipDoamin parameter Command Injection Attempt (CVE-2022-26187)"; flow:established,to_server; http.method; content:"POST"; http.uri; bsize:20; content:"/cgi-bin/cstecgi.cgi"; http.request_body; content:"|22|topicurl|22 3a|"; content:"|22|setting/setDiagnosisCfg|22|"; within:30; fast_pattern; content:"|22|ipDoamin|22 3a|"; pcre:"/^[^\x26]*?(?:(?:\x3b|%3[Bb])|(?:\x0a|%0[Aa])|(?:\x60|%60)|(?:\x7c|%7[Cc])|(?:\x24|%24))+/R"; reference:url,github.com/doudoudedi/TOTOLINK_N600R_Command_Injection/blob/main/TOTOLINK-N600R-Command-Injection.md; reference:cve,2022-26187; classtype:attempted-admin; sid:2061799; rev:1; metadata:affected_product TOTOLINK, attack_target Networking_Equipment, tls_state plaintext, created_at 2025_04_22, cve CVE_2022_26187, deployment Perimeter, deployment Internal, performance_impact Low, confidence High, signature_severity Major, tag Exploit, updated_at 2025_04_22, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;)
  • Look for HTTP POST requests to /cgi-bin/cstecgi.cgi with a JSON body containing the topicurl value 'setting/setDiagnosisCfg' and the 'ipDoamin' parameter — note the intentional typo in the parameter name.
  • Flag injection characters (semicolon, newline, backtick, pipe, dollar sign) in the ipDoamin parameter value, including both raw and URL-encoded forms: %3B, %0A, %60, %7C, %24.
  • The vulnerability is in the pingCheck function; monitor for OS command execution originating from the TOTOLINK N600R web management process.
  • Traffic is expected over plaintext HTTP (not TLS); deploy detection at the network perimeter and internally.
  • ·The vulnerable firmware version is specifically V4.3.0cu.7570_B20200620; detections should be scoped to devices running this exact build.
  • ·The Snort/Suricata rule (sid:2061799) uses a fixed URI bsize of 20 bytes for /cgi-bin/cstecgi.cgi; ensure your IDS/IPS supports the bsize keyword to avoid false negatives.
  • ·The parameter name 'ipDoamin' is a typo (not 'ipDomain') as it appears in the actual firmware/CGI handler; signatures must match this misspelled name exactly.

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
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