Coverage › CVE-2023-20118

CVE-2023-20118 Mapped Sigma

Cisco Small Business RV Series Routers Command Injection Vulnerability

Vendor / product

Cisco — Small Business RV Series Routers

Description (CISA)

Multiple Cisco Small Business RV Series Routers contains a command injection vulnerability in the web-based management interface. Successful exploitation could allow an authenticated, remote attacker to gain root-level privileges and access unauthorized data.

Added to KEV

2025-03-03

Due date

2025-03-24

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Known ransomware use

Unknown

CWE

CWE-77

CISA notes

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbr042-multi-vuln-ej76Pke5
https://nvd.nist.gov/vuln/detail/CVE-2023-20118

Elsewhere

cve.org · NVD · CISA KEV · JSON

ATT&CK techniques · CTID Mappings Explorer, ATT&CK 16.1, KEV snapshot 2025-07-28

4 mapping objects across 4 techniques. exploitation technique states how the vulnerability is exploited; primary and secondary impact state what exploitation achieves. They are different claims and are labelled as such.

Detection chain · ATT&CK Enterprise v19.2 detection strategies, analytics, log sources

T1059 Command and Scripting Interpreter primary impact

• DET0516 Behavioral Detection of Command and Scripting Interpreter Abuse
  AN1428 Windows

  Detects the execution of scripting or command interpreters (e.g., powershell.exe, cmd.exe, wscript.exe) outside expected administrative time windows or from abnormal user contexts, often followed by encoded/obfuscated arguments or secondary execution events.

  WinEventLog:Sysmon EventCode=1 → DC0032 Process Creation

  Tunable: CommandLinePattern ParentProcessName TimeWindow
  AN1429 Linux

  Detects use of shell interpreters (e.g., bash, sh, python, perl) initiated by users or processes not normally executing them, especially when chaining suspicious utilities like netcat, curl, or ssh.

  auditd:SYSCALL execve → DC0032 Process Creation

  Tunable: InterpreterName UserContext ExecutionChainLength
  AN1430 macOS

  Detects launch of command-line interpreters via Terminal, Automator, or hidden osascript, especially when parent process lineage deviates from user-initiated applications.

  macos:unifiedlog log stream --info --predicate 'eventMessage CONTAINS "exec"' → DC0032 Process Creation

  Tunable: LaunchAgentName ScriptName TerminalAppUsage
  AN1431 ESXi

  Detects use of 'esxcli system' or direct interpreter commands (e.g., busybox shell) invoked from SSH or host terminal unexpectedly.

  esxi:vobd shell session start → DC0064 Command Execution

  Tunable: ShellEnabledFlag SSHContext
  AN1432 Network Devices

  Identifies CLI interpreter access (e.g., Cisco IOS, Juniper JUNOS) via enable mode or scripting-capable sessions used by uncommon accounts or from unknown IPs.

  networkdevice:cli shell command → DC0064 Command Execution

  networkdevice:syslog authentication & authorization → DC0002 User Account Authentication

  Tunable: UserRole DeviceType

Sigma rules tagged attack.t1059 (95)

All 95 rules on the technique page →

T1068 Exploitation for Privilege Escalation exploitation technique

• DET0514 Detection Strategy for Exploitation for Privilege Escalation
  AN1419 Windows

  Detects exploitation attempts targeting vulnerable kernel drivers or OS components, often followed by unusual process or token behavior.

  WinEventLog:Sysmon EventCode=6 → DC0079 Driver Load

  WinEventLog:Sysmon EventCode=1 → DC0032 Process Creation

  WinEventLog:Security EventCode=4672 → DC0088 Logon Session Metadata

  Tunable: DriverNamePattern TimeWindow ParentProcessPath
  AN1420 Linux

  Detects escalation via vulnerable setuid binaries or kernel modules, often chained with unusual access to /proc/kallsyms or /dev/kmem.

  auditd:SYSCALL execve → DC0032 Process Creation

  auditd:SYSCALL ACCESS → DC0035 Process Access

  auditd:SYSCALL dmesg → DC0016 Module Load

  Tunable: SetUIDBinaryList TimeWindow EffectiveUIDThreshold
  AN1421 macOS

  Detects use of vulnerable kernel extensions or entitlements abused via setuid or AppleScript injection chains.

  macos:unifiedlog process:exec and kext load events → DC0032 Process Creation

  macos:endpointsecurity ES_EVENT_TYPE_NOTIFY_KEXTLOAD → DC0016 Module Load

  Tunable: EntitlementList TimeWindow
  AN1422 Containers

  Detects container breakout behavior via exploitation (e.g., DirtyPipe, CVE-2022-0847), followed by host OS interaction or escalated capability assignment.

  auditd:SYSCALL capset or setns → DC0067 Logon Session Creation

  containerd:runtime e.g., containerd, Docker events → DC0091 Container Enumeration

  Tunable: NamespaceEscapePattern TimeWindow

Sigma rules tagged attack.t1068 (31)

All 31 rules on the technique page →

T1078 Valid Accounts exploitation technique

• DET0560 Detection of Valid Account Abuse Across Platforms
  AN1543 Windows

  Detection of compromised or misused valid accounts via anomalous logon patterns, abnormal logon types, and inconsistent geographic or time-based activity across Windows endpoints.

  WinEventLog:Security EventCode=4624 → DC0067 Logon Session Creation

  WinEventLog:Security EventCode=4776, 4625 → DC0002 User Account Authentication

  WinEventLog:Sysmon EventCode=1 → DC0032 Process Creation

  Tunable: LogonType TimeWindow GeoIPMismatch
  AN1544 Linux

  Detection of valid account misuse through SSH logins, sudo/su abuse, and service account anomalies outside expected patterns.

  auditd:SYSCALL execve → DC0032 Process Creation

  NSM:Connections sshd or PAM logins → DC0002 User Account Authentication

  Tunable: UserContext HostDensityThreshold LoginMethod
  AN1545 macOS

  Detection of interactive and remote logins by service accounts or users at unusual times, with unexpected child process activity.

  macos:unifiedlog loginwindow, sshd → DC0088 Logon Session Metadata

  macos:unifiedlog exec logs → DC0032 Process Creation

  Tunable: LoginOrigin ProcessTreeDepth
  AN1546 Identity Provider

  Detection of valid account abuse in IdP logs via geographic anomalies, impossible travel, risky sign-ins, and multiple MFA attempts or failures.

  saas:okta Sign-in logs / audit events → DC0002 User Account Authentication

  Tunable: MFAFailureCount RiskScoreThreshold IPGeoVelocity
  AN1547 Containers

  Detection of containerized service accounts or compromised kubeconfigs being used for cluster access from unexpected nodes or IPs.

  kubernetes:audit authentication.k8s.io → DC0002 User Account Authentication

  Tunable: ServiceAccountScope ClusterIPWhitelist

Sigma rules tagged attack.t1078 (56)

All 56 rules on the technique page →

T1505.003 Web Shell secondary impact

• DET0394 Web Shell Detection via Server Behavior and File Execution Chains
  AN1108 Windows

  Unexpected file creation in web directories followed by web server processes (e.g., w3wp.exe) spawning command shells or script interpreters (e.g., cmd.exe, powershell.exe)

  WinEventLog:Sysmon EventCode=11 → DC0039 File Creation

  WinEventLog:Sysmon EventCode=1 → DC0032 Process Creation

  WinEventLog:Security EventCode=4624, 4648 → DC0067 Logon Session Creation

  NSM:Flow Inbound HTTP POST with suspicious payload size or user-agent → DC0085 Network Traffic Content

  Tunable: WebRootPath ParentProcess
  AN1109 Linux

  File creation of unauthorized script (e.g., .php, .sh) in /var/www/html followed by execution of unexpected system utilities (e.g., curl, bash, nc) by apache/nginx

  auditd:SYSCALL new file created in /var/www/html, /srv/http, or similar web root → DC0039 File Creation

  auditd:SYSCALL apache2 or nginx spawning sh, bash, or python interpreter → DC0032 Process Creation

  NSM:Flow POST requests to .php, .jsp, .aspx files with high entropy body → DC0085 Network Traffic Content

  Tunable: WebRootPath PayloadEntropyThreshold TimeWindow
  AN1110 macOS

  Web servers (e.g., httpd) spawning abnormal processes post file upload into /Library/WebServer/Documents or /usr/local/var/www

  macos:unifiedlog httpd spawning bash, zsh, python, or osascript → DC0032 Process Creation

  auditd:SYSCALL file write operations in /Library/WebServer/Documents → DC0061 File Modification

  Tunable: InterpreterName ExecutionParent

Sigma rules tagged attack.t1505.003 (35)

All 35 rules on the technique page →