Coverage › CVE-2024-21893

CVE-2024-21893 Mapped Sigma

Ivanti Connect Secure, Policy Secure, and Neurons Server-Side Request Forgery (SSRF) Vulnerability

Vendor / product

Ivanti — Connect Secure, Policy Secure, and Neurons

Description (CISA)

Ivanti Connect Secure (ICS, formerly known as Pulse Connect Secure), Ivanti Policy Secure, and Ivanti Neurons contain a server-side request forgery (SSRF) vulnerability in the SAML component that allows an attacker to access certain restricted resources without authentication.

Added to KEV

2024-01-31

Due date

2024-02-02

Required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Known ransomware use

Known

CWE

CWE-918

CISA notes

https://forums.ivanti.com/s/article/KB-CVE-2023-46805-Authentication-Bypass-CVE-2024-21887-Command-Injection-for-Ivanti-Connect-Secure-and-Ivanti-Policy-Secure-Gateways?language=en_US
https://nvd.nist.gov/vuln/detail/CVE-2024-21893

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

T1078 Valid Accounts primary impact

• 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 →

T1190 Exploit Public-Facing Application exploitation technique

• DET0080 Exploit Public-Facing Application – multi-signal correlation (request → error → post-exploit process/egress)
  AN0219 Windows

  Adversary sends crafted HTTP/S (or other service) input to an Internet-facing app (IIS/ASP.NET, API, device portal). Chain: (1) abnormal request patterns to public endpoint → (2) elevated 4xx/5xx or unusual methods/paths → (3) server process (w3wp.exe/other service) spawns shell/LOLbins or loads non-standard modules → (4) optional outbound callback from the host/container.

  ApplicationLog:IIS IIS W3C logs in C:\inetpub\logs\LogFiles\W3SVC* (spikes in 5xx, RCE/SQLi/path traversal/JNDI patterns) → DC0038 Application Log Content

  WinEventLog:Sysmon EventCode=1 → DC0032 Process Creation

  WinEventLog:Sysmon EventCode=7 → DC0016 Module Load

  WinEventLog:Sysmon EventCode=3, 22 → DC0082 Network Connection Creation

  Tunable: PublicVIPs SuspiciousPatterns ErrorRateThreshold TimeWindow AllowedChildList
  AN0220 Linux

  Adversary exploits Apache/Nginx/app servers. Chain: (1) suspicious requests in access logs → (2) spike of 5xx or WAF blocks → (3) web server or interpreter (apache2/nginx/php-fpm/node/python) spawns /bin/sh, curl, wget, socat, or writes webshell → (4) outbound callback.

  ApplicationLog:WebServer /var/log/httpd/access_log, /var/log/apache2/access.log, /var/log/nginx/access.log with exploit indicators and burst errors → DC0038 Application Log Content

  auditd:SYSCALL execve → DC0032 Process Creation

  NSM:Flow HTTP payloads with SQLi/LFI/JNDI/deserialization indicators → DC0085 Network Traffic Content

  Tunable: WebProcList ChildToolList BurstThreshold TimeWindow
  AN0221 macOS

  Adversary targets macOS-hosted public services (e.g., nginx, node). Chain: suspicious inbound request → service crash/5xx → service spawns shell or writes file → new outbound connection.

  macos:unifiedlog App/web server logs ingested via unified logging or filebeat (nginx/apache/node). → DC0038 Application Log Content

  macos:unifiedlog exec events where web process starts a shell/tooling → DC0032 Process Creation

  NSM:Flow outbound egress from web host after suspicious request → DC0085 Network Traffic Content

  Tunable: ServiceList TimeWindow
  AN0222 Containers

  Adversary exploits containerized app via ingress or service. Chain: (1) suspicious request in ingress/app logs → (2) container process spawns a shell/exec/sidecar (kubectl exec/docker exec) → (3) egress to Internet or metadata service (169.254.169.254).

  ApplicationLog:Ingress Kubernetes NGINX/Envoy ingress controller logs with anomalous payloads and 5xx spikes → DC0038 Application Log Content

  docker:events Docker/Kubernetes audit of exec/attach (kubectl exec) or unexpected child processes inside container → DC0032 Process Creation

  NSM:Flow Requests towards cloud metadata or command & control from pod IPs → DC0085 Network Traffic Content

  Tunable: IngressNamespaces MetadataEndpoints TimeWindow
  AN0223 IaaS

  Adversary targets cloud-hosted public endpoints. Chain: (1) ALB/ELB/Cloud LB logs show exploit-like inputs or error spikes → (2) workload spawns shell or reaches metadata API → (3) egress to new external hosts.

  ALB:HTTPLogs AWS ALB/ELB/GCP/Azure Application Gateway HTTP logs with unusual methods, long URIs, serialized payloads, 4xx/5xx bursts → DC0085 Network Traffic Content

  AWS:VPCFlowLogs VPC/NSG flow logs for pod/instance egress to Internet or metadata → DC0078 Network Traffic Flow

  Tunable: LBProjects ErrorBurst
  AN0224 ESXi

  Adversary exploits exposed OpenSLP on ESXi or vCenter public endpoints. Chain: inbound request pattern to mgmt service → hostd/vpxd error/crash/restart → unexpected process behavior or datastore access → outbound callback.

  esxi:hostd /var/log/hostd.log anomalies (faults, crashes, restarts) around inbound connections → DC0038 Application Log Content

  NSM:Flow Connections to TCP 427 (SLP) or vCenter web services from untrusted sources → DC0085 Network Traffic Content

  Tunable: MgmtCIDR TimeWindow
  AN0225 Network Devices

  Adversary exploits public admin services on routers/firewalls/switches. Chain: anomalous HTTP/SNMP/SmartInstall inputs → device syslog errors/restarts → config changes/CLI spawn → egress to attacker C2.

  networkdevice:controlplane Syslog from edge devices with HTTP 500s on mgmt portal, SmartInstall events, unexpected CLI commands → DC0038 Application Log Content

  NSM:Flow NetFlow/sFlow for odd egress to Internet from mgmt plane → DC0085 Network Traffic Content

  Tunable: MgmtPorts TrustedAdmins

Sigma rules tagged attack.t1190 (149)

All 149 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 →

T1555 Credentials from Password Stores secondary impact

• DET0430 Detect Credentials Access from Password Stores
  AN1198 Windows

  Monitors suspicious access to password stores such as LSASS, DPAPI, Windows Credential Manager, or browser credential databases. Detects anomalous process-to-process access (e.g., Mimikatz accessing LSASS) and correlation of credential store file reads with execution of non-standard processes.

  WinEventLog:Sysmon EventCode=10 → DC0035 Process Access

  WinEventLog:Security EventCode=4663, 4670, 4656 → DC0055 File Access

  WinEventLog:Sysmon EventCode=1 → DC0032 Process Creation

  Tunable: TargetProcesses KeywordPatterns
  AN1199 Linux

  Detects access to known password store files (e.g., /etc/shadow, GNOME Keyring, KWallet, browser credential databases). Monitors anomalous process read attempts and suspicious API calls that attempt to extract stored credentials.

  auditd:SYSCALL open/read → DC0055 File Access

  auditd:EXECVE execve → DC0032 Process Creation

  Tunable: MonitoredFiles SuspiciousCommands
  AN1200 macOS

  Monitors Keychain database access and suspicious invocations of security and osascript utilities. Correlates process execution with attempts to dump or unlock Keychain data.

  macos:unifiedlog access to keychain database → DC0055 File Access

  macos:unifiedlog execution of security or osascript → DC0032 Process Creation

  Tunable: AllowedApplications AlertThreshold
  AN1201 IaaS

  Detects attempts to access or enumerate cloud password/secrets storage services such as AWS Secrets Manager, Azure Key Vault, or GCP Secret Manager. Monitors API calls for abnormal enumeration or bulk retrieval of secrets.

  AWS:CloudTrail GetSecretValue → DC0083 Cloud Service Enumeration

  AWS:CloudTrail Decrypt → DC0021 OS API Execution

  Tunable: UserContext AccessThreshold

Sigma rules tagged attack.t1555 (8)