Vulnerabilities > CVE-2007-6181 - Buffer Errors vulnerability in Redhat Cygwin 1.5.19/1.5.7/1.5.71

047910
CVSS 8.5 - HIGH
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
SINGLE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
network
redhat
CWE-119
nessus
NVD
Published: 2007-11-30
Updated: 2018-10-26

Summary

Heap-based buffer overflow in cygwin1.dll in Cygwin 1.5.7 and earlier allows context-dependent attackers to execute arbitrary code via a filename with a certain length, as demonstrated by a remote authenticated user who uses the SCP protocol to send a file to the Cygwin machine, and thereby causes scp.exe on this machine to execute, and then overwrite heap memory with characters from the filename. NOTE: it is also reported that a related issue might exist in 1.5.7 through 1.5.19.

Vulnerable Configurations

Part Description Count
Application
Redhat
4

Common Weakness Enumeration (CWE)

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 idCYGWIN_1_5_24.NASL
descriptionCygwin, a Linux-like environment for Windows, is installed on the remote host. The version of Cygwin installed on the remote host is affected by a heap-based buffer overflow vulnerability involving a filename length check. Using a filename between 233 and 239 characters, an attacker who can create a file on the remote can leverage this issue to execute arbitrary code on the affected host subject to the privileges under which Cygwin operates.
last seen2020-06-01
modified2020-06-02
plugin id28330
published2007-11-27
reporterThis script is Copyright (C) 2007-2018 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/28330
titleCygwin < 1.5.24 cygwin1.dll Crafted Filename Handling Overflow
code
#
#  (C) Tenable Network Security, Inc.
#


include("compat.inc");

if (description)
{
  script_id(28330);
  script_version("1.13");
 script_cvs_date("Date: 2018/11/15 20:50:26");

  script_cve_id("CVE-2007-6181");
  script_bugtraq_id(26557);

  script_name(english:"Cygwin < 1.5.24 cygwin1.dll Crafted Filename Handling Overflow");
  script_summary(english:"Checks version of cygwin1.dll");

 script_set_attribute(attribute:"synopsis", value:
"The remote Windows host contains an application that is prone to a
buffer overflow vulnerability.");
 script_set_attribute(attribute:"description", value:
"Cygwin, a Linux-like environment for Windows, is installed on the
remote host.

The version of Cygwin installed on the remote host is affected by a
heap-based buffer overflow vulnerability involving a filename length
check. Using a filename between 233 and 239 characters, an attacker
who can create a file on the remote can leverage this issue to execute
arbitrary code on the affected host subject to the privileges under
which Cygwin operates.");
 script_set_attribute(attribute:"see_also", value:"https://www.securityfocus.com/archive/1/484153/30/0/threaded");
 script_set_attribute(attribute:"see_also", value:"http://cygwin.com/ml/cygwin-developers/2007-11/msg00001.html" );
 script_set_attribute(attribute:"solution", value:"Upgrade to Cygwin 1.5.24 as that version is reportedly not affected.");
 script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:S/C:C/I:C/A:C");
 script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
 script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
 script_set_attribute(attribute:"exploit_available", value:"false");
 script_cwe_id(119);

 script_set_attribute(attribute:"plugin_publication_date", value:"2007/11/27");

script_set_attribute(attribute:"plugin_type", value:"local");
script_end_attributes();


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

  script_copyright(english:"This script is Copyright (C) 2007-2018 Tenable Network Security, Inc.");

  script_dependencies("smb_hotfixes.nasl");
  script_require_keys("SMB/Registry/Enumerated");
  script_require_ports(139, 445);

  exit(0);
}


include("smb_func.inc");
include("smb_hotfixes.inc");
include("audit.inc");


if (!get_kb_item("SMB/Registry/Enumerated")) exit(0);


# 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');
rc = NetUseAdd(login:login, password:pass, domain:domain, share:"IPC$");
if (rc != 1) {
  NetUseDel();
  exit(0);
}


# Connect to remote registry.
hklm = RegConnectRegistry(hkey:HKEY_LOCAL_MACHINE);
if (isnull(hklm))
{
  NetUseDel();
  exit(0);
}


# Make sure it's installed.
path = NULL;

key = "SOFTWARE\Cygnus Solutions\Cygwin\mounts v2\/usr/bin";
key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
if (!isnull(key_h))
{
  value = RegQueryValue(handle:key_h, item:"native");
  if (!isnull(value))
  {
    path = value[1];
    path = str_replace(find:'/', replace:'\\', string:path);
  }

  RegCloseKey(handle:key_h);
}
RegCloseKey(handle:hklm);
if (isnull(path))
{
  NetUseDel();
  exit(0);
}


# Grab the file version of the affected file.
share = ereg_replace(pattern:"^([A-Za-z]):.*", replace:"\1$", string:path);
dll = ereg_replace(pattern:"^[A-Za-z]:(.*)", replace:"\1\cygwin1.dll", string:path);
NetUseDel(close:FALSE);

rc = NetUseAdd(login:login, password:pass, domain:domain, share:share);
if (rc != 1)
{
  NetUseDel();
  exit(0);
}

fh = CreateFile(
  file:dll,
  desired_access:GENERIC_READ,
  file_attributes:FILE_ATTRIBUTE_NORMAL,
  share_mode:FILE_SHARE_READ,
  create_disposition:OPEN_EXISTING
);
ver = NULL;
if (!isnull(fh))
{
  ver = GetFileVersion(handle:fh);
  CloseFile(handle:fh);
}
NetUseDel();


# Check the version number.
if (!isnull(ver))
{
  # nb: 1005.24.0.0 is the file version from version 1.5.24.
  fix = split("1005.24.0.0", sep:'.', keep:FALSE);
  for (i=0; i<4; i++)
    fix[i] = int(fix[i]);

  for (i=0; i<max_index(ver); i++)
    if ((ver[i] < fix[i]))
    {
      security_hole(port);
      break;
    }
    else if (ver[i] > fix[i])
      break;
}

References