cbcvebase.
CVE-2022-26210
published 2022-03-15

CVE-2022-26210: Totolink A830R V5.9c.4729_B20191112, A3100R V4.1.2cu.5050_B20200504, A950RG V4.1.2cu.5161_B20200903, A800R V4.1.2cu.5137_B20200730, A3000RU…

PriorityP187critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWVulnCheck KEV
Exploited in the wild
EPSS
5.75%
92.2th percentile
Totolink A830R V5.9c.4729_B20191112, A3100R V4.1.2cu.5050_B20200504, A950RG V4.1.2cu.5161_B20200903, A800R V4.1.2cu.5137_B20200730, A3000RU V5.9c.5185_B20201128, and A810R V4.1.2cu.5182_B20201026 were discovered to contain a command injection vulnerability in the function setUpgradeFW, via the FileName parameter. This vulnerability allows attackers to execute arbitrary commands via a crafted request.

Affected

6 ranges
VendorProductVersion rangeFixed in
totolinka3000ru_firmware
totolinka3100r_firmware
totolinka800r_firmware
totolinka810r_firmware
totolinka830r_firmware
totolinka950rg_firmware

Detection & IOCsextracted from sources · hover to see the quote

url/cgi-bin/cstecgi.cgi
commandsetUpgradeFW
snort
alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (msg:"ET EXPLOIT Totolink - Command Injection Attempt Inbound (CVE-2022-26210)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/cgi-bin/cstecgi.cgi"; http.request_body; content:"setUpgradeFW"; fast_pattern; content:"FileName|3a 20 3a|"; distance:0; pcre:"/^.{0,20}[\x3b\x0a\x26\x60\x7c\x24]/R"; reference:cve,2022-26210; classtype:attempted-admin; sid:2035744; rev:4; metadata:attack_target Networking_Equipment, created_at 2022_04_05, cve CVE_2022_26210, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, updated_at 2024_11_29, mitre_tactic_id TA0008, mitre_tactic_name Lateral_Movement, mitre_technique_id T1210, mitre_technique_name Exploitation_Of_Remote_Services;)
bytes
FileName|3a 20 3a|
  • Exploit arrives as an inbound HTTP POST request to /cgi-bin/cstecgi.cgi with 'setUpgradeFW' in the request body and a malformed FileName parameter containing shell metacharacters (;, newline, &, backtick, |, $) immediately after the 'FileName: :' pattern.
  • MITRE mapping: Lateral Movement (TA0008) / Exploitation of Remote Services (T1210) — target is Networking Equipment, indicating this is exploited against routers from the network perimeter or internally.
  • Vulnerable function is setUpgradeFW; the injection point is the FileName parameter. Any request body containing 'setUpgradeFW' with shell metacharacters in the FileName field should be treated as a high-confidence exploit attempt.
  • ·The Snort/Suricata rule (ET sid:2035744 rev:4) was last updated 2024-11-29; ensure your ruleset is current to use the latest revision.
  • ·Rule is designed for both Perimeter and Internal deployment — it should be applied at network egress/ingress AND on internal segments to catch lateral movement scenarios.

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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