Symantec Messaging Gateway SSH with backdoor user account + privilege escalation to root due to very old Kernel
Summary
Name: Symantec Messaging Gateway – SSH with backdoor user account + privilege escalation to root due to very old Kernel
Release Date: 30 November 2012
Reference: NGS00267
Discoverer: Ben Williams
Vendor: Symantec
Vendor Reference:
Systems Affected: Symantec Messaging Gateway 9.5.3-3
Risk: High
Status: Published
TimeLine
Discovered: 18 April 2012
Released: 18 April 2012
Approved: 29 April 2012
Reported: 30 April 2012
Fixed: 27 August 2012
Published: 30 November 2012
Description
I. VULNERABILITY
Symantec Messaging Gateway 9.5.3-3 – SSH with backdoor user account + privilege escalation to root due to very old Kernel
II. BACKGROUND
Symantec Messaging Gateway 9.5.3-3 is the latest version, of their Email Security Appliance
III. DESCRIPTION
The “admin” SSH account has a restricted shell, and the password is set by the administrator during setup.
However, there is another SSH account “support” which has a default password, which is not changed during installation, and does not seem to be mentioned in the Symantec documentation as far as I can see (Installation Guide, Administration Guide or Command-line Guide). This account has a very easy-to-guess password, but many administrators may not know it exists.
Additionally, the Linux Kernel on the appliance has not been updated since late 2007 (almost 5 years) so suffers from multiple privilege escalation issues (as do other old packages on the operating system) so if SSH is accessible to an attacker, it is possible for them to login and escalate to root.
Technical Details
IV. PROOF OF CONCEPT
Both the install wizard and the documentation prompt the administrator to change the password for the “admin” account, for both the UI and for SSH to the operating system. This admin account can SSH in to the appliance, with the new chosen password, and has a restricted shell environment where only certain application administration commands are possible.
It is not possible to login as root. However, there is another account “support” which has a default password of “symantec” which is not mentioned anywhere in the installer or documentation (as far as I can see) and the password is not changed as part of the installation process. This account is able to login to the OS via SSH, and does not have a restricted shell environment.
Additionally, the Linux Kernel is very old (2007) so suffers from multiple privilege escalation issues.
[+] Results for kernel version 2.6.18-274.3.1.2.el5_sms
Potential exploits:
- Linux Kernel BCM Local Root Exploit
CVE: CVE-2010-2959
Affects kernels: 2.6.0-2.6.36rc1
Exploits:
http://www.exploit-db.com/exploits/14814 -
Linux Kernel RDS protocol Local Root Exploit
CVE: CVE-2010-3904
Affects kernels: 2.6.0-2.6.36rc8
Exploits:
http://www.exploit-db.com/exploits/15285 -
Linux Kernel econet_sendmsg() – half-nelson Local Root Exploit
CVE: CVE-2010-3848
Affects kernels: 2.6.0-2.6.36.2
Exploits:
http://www.exploit-db.com/exploits/17787
* Linux Kernel Unknown Local Root Exploit
CVE: CVE-None
Affects kernels: 2.6.18-2.6.20
Exploits:
http://www.exploit-db.com/exploits/10613 -
Linux Kernel sock_sendpage() (Wunderbar Emporium) Local Root Exploit
CVE: CVE-2009-2692
Affects kernels: 2.6.0-2.6.31rc3
Exploits:
http://www.exploit-db.com/exploits/9641
http://www.exploit-db.com/exploits/9545
http://www.exploit-db.com/exploits/9479
http://www.exploit-db.com/exploits/9436
http://www.exploit-db.com/exploits/9435
http://www.grsecurity.net/~spender/enlightenment.tgz -
Linux Kernel pipe.c (MooseCox) Local Root Exploit
CVE: CVE-2009-3547
Affects kernels: 2.6.0-2.6.32rc5
Exploits:
http://www.exploit-db.com/exploits/10018
http://www.grsecurity.net/~spender/enlightenment.tgz -
Linux Kernel ReiserFS xattr Local Root Exploit
CVE: CVE-2010-1146
Affects kernels: 2.6.0-2.6.34rc3
Exploits:
http://www.exploit-db.com/exploits/12130 -
Linux Kernel vmsplice Local Root Exploit
CVE: CVE-2008-0009
Affects kernels: 2.6.17-2.6.24.1
Exploits:
http://www.exploit-db.com/exploits/5092
http://www.exploit-db.com/exploits/5093 -
Linux Kernel ec_dev_ioctl() – half-nelson Local Root Exploit
CVE: CVE-2010-3850
Affects kernels: 2.6.0-2.6.36.2
Exploits:
http://www.exploit-db.com/exploits/17787
http://www.exploit-db.com/exploits/15704 -
Linux Kernel ACPI custom_method Local Root Exploit
CVE: CVE-2010-4347
Affects kernels: 2.6.0-2.6.37rc2
Exploits:
http://www.exploit-db.com/exploits/15774 -
Linux Kernel ftruncate()/open() Local Root Exploit
CVE: CVE-2008-4210
Affects kernels: 2.6.0-2.6.22
Exploits:
http://www.exploit-db.com/exploits/6851 -
Linux Kernel put_user() – full-nelson Local Root Exploit
CVE: CVE-2010-4258
Affects kernels: 2.6.0-2.6.37
Exploits:
http://www.exploit-db.com/exploits/15704 -
Linux Kernel sock_no_sendpage() – full-nelson Local Root Exploit
CVE: CVE-2010-3849
Affects kernels: 2.6.0-2.6.37
Exploits:
http://www.exploit-db.com/exploits/15704 -
Linux Kernel ipc – half-nelson Local Root Exploit
CVE: CVE-2010-4073
Affects kernels: 2.6.0-2.6.37rc1
Exploits:
http://www.exploit-db.com/exploits/17787 -
Linux Kernel SELinux/RHEL5 (Cheddar Bay) Local Root Exploit
CVE: CVE-None
Affects kernels: 2.6.9-2.6.30
Exploits:
http://www.exploit-db.com/exploits/9208
http://www.exploit-db.com/exploits/9191
http://www.grsecurity.net/~spender/enlightenment.tgz -
Linux Kernel exit_notify() Local Root Exploit
CVE: CVE-2009-1337
Affects kernels: 2.6.0-2.6.29
Exploits:
http://www.exploit-db.com/exploits/8369 -
Linux Kernel system call emulation Local Root Exploit
CVE: CVE-2007-4573
Affects kernels: 2.6.0-2.6.22.7
Exploits:
http://www.exploit-db.com/exploits/4460 -
Linux Kernel set_selection() UTF-8 Off By One Local Root Exploit
CVE: CVE-2009-1046
Affects kernels: 2.6.0-2.6.28.3
Exploits:
http://www.exploit-db.com/exploits/9083
Fix Information
An updated version of the software has been released to address the vulnerability:
http://www.symantec.com/security_response/securityupdates/detail.jsp?fid=security_advisory pvid=security_advisory year=2012 suid=20120827_00