Vulnerabilities > CVE-2017-6669 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Cisco Webex Advanced Recording Format Player 29.10

047910
CVSS 6.8 - MEDIUM
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
network
cisco
CWE-119
nessus

Summary

Multiple buffer overflow vulnerabilities exist in the Cisco WebEx Network Recording Player for Advanced Recording Format (ARF) files. An attacker could exploit these vulnerabilities by providing a user with a malicious ARF file via email or URL and convincing the user to launch the file. Exploitation of these vulnerabilities could cause an affected player to crash and, in some cases, could allow arbitrary code execution on the system of a targeted user. The Cisco WebEx Network Recording Player is an application that is used to play back WebEx meeting recordings that have been recorded on the computer of an online meeting attendee. The player can be automatically installed when the user accesses a recording file that is hosted on a WebEx server. The following client builds are affected by this vulnerability: Cisco WebEx Business Suite (WBS29) client builds prior to T29.13.130, Cisco WebEx Business Suite (WBS30) client builds prior to T30.17, Cisco WebEx Business Suite (WBS31) client builds prior to T31.10. Cisco Bug IDs: CSCvc47758 CSCvc51227 CSCvc51242.

Vulnerable Configurations

Part Description Count
Application
Cisco
1

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.

Nessus

NASL familyWindows
NASL idCISCO-SA-20170621-WNRP.NASL
descriptionThe version of Cisco WebEx Network Recording Player installed on the remote host is affected by a remote code execution vulnerability due to multiple buffer overflow conditions in the Advanced Recording Format (ARF) file player. An unauthenticated, remote attacker can exploit this, by convincing a user to open a specially crafted ARF file using email or a URL, to cause a denial of service condition or the execution of arbitrary code.
last seen2020-06-01
modified2020-06-02
plugin id101298
published2017-07-07
reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/101298
titleCisco WebEx Network Recording Player ARF File RCE (cisco-sa-20170621-wnrp)
code
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(101298);
  script_version("1.6");
  script_cvs_date("Date: 2019/11/12");

  script_cve_id("CVE-2017-6669");
  script_bugtraq_id(99196);
  script_xref(name:"CISCO-BUG-ID", value:"CSCvc47758");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvc51227");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvc51242");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20170621-wnrp");

  script_name(english:"Cisco WebEx Network Recording Player ARF File RCE (cisco-sa-20170621-wnrp)");
  script_summary(english:"Checks WebEx file version numbers.");

  script_set_attribute(attribute:"synopsis", value:
"The video player installed on the remote Windows host is affected by a
remote code execution vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Cisco WebEx Network Recording Player installed on the
remote host is affected by a remote code execution vulnerability due
to multiple buffer overflow conditions in the Advanced Recording
Format (ARF) file player. An unauthenticated, remote attacker can
exploit this, by convincing a user to open a specially crafted ARF
file using email or a URL, to cause a denial of service condition or
the execution of arbitrary code.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170621-wnrp
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?43983fb7");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version of WebEx Network Recording
Player referenced in Cisco advisory cisco-sa-20170621-wnrp.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-6669");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/06/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/06/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/07/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:webex_advanced_recording_format_player");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows");

  script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("webex_player_installed.nasl");
  script_require_keys("SMB/ARF Player/path");
  script_require_ports(139, 445);

  exit(0);
}

include("audit.inc");
include("smb_func.inc");
include("smb_hotfixes.inc");
include("smb_hotfixes_fcheck.inc");
include("smb_reg_query.inc");
include("misc_func.inc");

path = get_kb_item_or_exit('SMB/ARF Player/path');
app =  'Cisco WebEx Network Recording Player';
get_kb_item_or_exit("SMB/Registry/Enumerated");
ver = NULL;

# Connect to the appropriate share.
port = kb_smb_transport();
login = kb_smb_login();
pass = kb_smb_password();
domain = kb_smb_domain();

if (!smb_session_init())
  audit(AUDIT_FN_FAIL, "smb_session_init");

share = ereg_replace(pattern:"^([A-Za-z]):.*", replace:"\1$", string:path);
file_path = ereg_replace(pattern:"^[A-Za-z]:(.*)", replace:"\1", string:path);

rc = NetUseAdd(login:login, password:pass, domain:domain, share:share);
if (rc != 1)
{
  NetUseDel();
  audit(AUDIT_SHARE_FAIL, share);
}

fh = CreateFile(
  file               : file_path + "buildver.ini",
  desired_access     : GENERIC_READ,
  file_attributes    : FILE_ATTRIBUTE_NORMAL,
  share_mode         : FILE_SHARE_READ,
  create_disposition : OPEN_EXISTING
);

if (!isnull(fh))
{
  size = GetFileSize(handle:fh);
  if (size > 0)
  {
    blob = ReadFile(handle:fh, length:size, offset:0);
    ver = pregmatch(
      pattern : "ClientBuildVersionNumber=([0-9\.]+)",
      icase   : TRUE,
      string  : blob
    );
    if (!empty_or_null(ver))
      ver = ver[1];
    else
    {
      CloseFile(handle:fh);
      NetUseDel();
      audit(AUDIT_VER_FAIL, path + "buildver.ini");
    }
  }
  CloseFile(handle:fh);
}
NetUseDel();

if (empty_or_null(ver))
  audit(AUDIT_UNKNOWN_APP_VER, app);

if (ver =~ "^29\.")
{
  fix = "29.13.130.0";
  min = "29.0.0.0";
}
else if (ver =~ "^30\.")
{
  fix = "30.17.0.0";
  min = "30.0.0.0";
}
else if (ver =~ "^31\.")
{
  fix = "31.10.0.0";
  min = "31.0.0.0";
}
else audit(AUDIT_INST_VER_NOT_VULN, app, ver);

if (ver_compare(ver:ver, fix:fix, minver:min, strict:FALSE) <0)
{
  report = report_items_str(
    report_items:make_array(
      "Path", path,
      "Installed version", ver,
      "Fixed version", fix
    ),
    ordered_fields:make_list("Path", "Installed version", "Fixed version")
  );
  security_report_v4(port:port, severity:SECURITY_WARNING, extra:report);
}
else audit(AUDIT_INST_VER_NOT_VULN, app, ver);