Detect Fortinet FortiWeb OS Command Injection (CVE-2025-58034) in Sumo Logic CSE
Detects exploitation of CVE-2025-58034, an OS command injection vulnerability (CWE-78) in Fortinet FortiWeb. This KEV-listed vulnerability allows attackers to inject and execute arbitrary OS commands through FortiWeb's management or inspection interfaces, potentially leading to full appliance compromise, lateral movement, and persistent access to network segmentation points.
MITRE ATT&CK
Sumo Detection Query
_sourceCategory=*fortiweb* OR _sourceCategory=*fortinet*
| where (%"vendor"="Fortinet" OR %"product"="FortiWeb" OR _raw matches /(?i)fortiweb/)
| where (
%"uri" matches /.*;.*/ OR %"uri" matches /.*\|.*/ OR %"uri" matches /.*&&.*/
OR %"uri" matches /.*`.*/ OR %"uri" matches /.*\$\(.*/
OR %"request" matches /.*%3B.*/ OR %"request" matches /.*%7C.*/
OR _raw matches /(?i)(cmd_injection|os_command|command.injection|\/bin\/sh|\/bin\/bash)/
)
| parse regex field=_raw "src=(?P<src_ip>[\d\.]+)" nodrop
| parse regex field=_raw "dst=(?P<dst_ip>[\d\.]+)" nodrop
| parse regex field=_raw "url=(?P<url>[^\s]+)" nodrop
| count by src_ip, dst_ip, url, _sourceHost
| sort by _count desc
| fields src_ip, dst_ip, url, _sourceHost, _countSumo Logic search detecting OS command injection exploitation patterns in Fortinet FortiWeb logs, parsing source/destination IPs and injected URLs for analyst review.
Data Sources
Required Tables
False Positives & Tuning
- Web application traffic with legitimate special characters routed through FortiWeb
- Automated security scanners generating injection test payloads
- FortiWeb management API calls using shell-like syntax in parameters
- Third-party integrations that pass URL-encoded data through FortiWeb inspection
Other platforms for CVE-2025-58034
Testing Methodology
Validate this detection against 4 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1FortiWeb Command Injection via URI Path Semicolon Delimiter
Expected signal: FortiWeb access logs showing HTTP GET request to /cgi-bin/module;id;whoami from test IP. CommonSecurityLog entry with RequestURL containing semicolons.
- Test 2FortiWeb Command Injection via URL-Encoded Shell Metacharacters
Expected signal: FortiWeb logs showing request URL containing %3B sequence. Network proxy or WAF logs showing URL-decoded form with semicolons.
- Test 3Simulated Post-Exploitation Shell Spawn from Web Process
Expected signal: Process execution log showing /bin/bash spawned with parent process www-data or httpsd equivalent. File creation event for /tmp/fortiweb_compromise_marker.txt.
- Test 4FortiWeb Management Interface Credential Stuffing and Command Injection Attempt
Expected signal: FortiWeb authentication log showing POST to management API with injection payload in password field. CommonSecurityLog DeviceAction showing authentication attempt with anomalous credential content.
Response Playbook
Triage
- Identify the source IP and determine whether it belongs to a known administrator, security scanner, or external threat actor. Cross-reference with threat intelligence feeds and IP reputation services.
- Examine the raw HTTP request payload in FortiWeb logs for the specific URI path, query string, POST body, or HTTP header containing the injected shell metacharacters (e.g., `;`, `&&`, `|`, backtick, `$(`).
- Determine whether the injection attempt succeeded by correlating FortiWeb application logs with OS-level process execution logs: look for unexpected child processes spawned by httpsd or wad daemon (e.g., /bin/sh, /bin/bash, wget, curl, nc).
- Check FortiWeb system integrity indicators: look for new cron jobs, unauthorized user accounts, modified configuration files, or unexpected outbound network connections from the FortiWeb management IP.
Containment
- Immediately isolate the affected FortiWeb appliance from the network by disabling management access ACLs or placing it behind an emergency firewall rule blocking all inbound connections to management ports (80, 443, 8080, 8443) from unauthorized sources.
- Revoke all active administrative sessions on the FortiWeb appliance and rotate all credentials (admin passwords, API keys, certificates) stored on or associated with the device. Notify downstream systems that use FortiWeb for authentication or inspection.
Evidence Collection
- Capture and preserve full FortiWeb system logs (/var/log/), application logs, and traffic logs before any remediation. Export to a forensically sound, write-protected storage location with cryptographic hash verification.
- Collect a memory dump and disk image of the FortiWeb appliance if physically or virtually accessible, to preserve volatile artifacts such as injected command history, modified in-memory configurations, and active network connections (netstat -antp output).
Escalation Criteria
- !Escalate immediately to incident response if any successful OS command execution is confirmed (e.g., child shell process observed, unauthorized file creation, outbound C2 connection from FortiWeb IP), as this represents full appliance compromise.
- !Escalate if the FortiWeb appliance has access to internal network segments, as a compromised WAF is a high-value pivot point for lateral movement into protected application tiers, databases, or internal administrative networks.
Investigation Guide
Related Techniques
Forensic Artifacts
- >
FortiWeb access logs showing HTTP requests with shell metacharacters (;, &&, |, `, $()) in URI paths, query strings, or POST bodies - >
OS process execution logs on FortiWeb showing /bin/sh or /bin/bash spawned as children of httpsd or wad - >
Crontab entries (/var/spool/cron/crontabs/, /etc/cron.d/) added after the exploitation timestamp - >
New or modified files in /tmp, /var/tmp, or FortiWeb configuration directories created during the attack window - >
Outbound network connections from the FortiWeb management IP to external IPs not in the approved management network
Tuning Guidance
Start with a 7-day baseline of FortiWeb log volume and establish allowlists for known management IP ranges and authorized scanner IPs. Tune the URL pattern matching to exclude legitimate application paths that use semicolons or pipes in query parameters by adding `not (RequestURL startswith "/api/allowed-path")` clauses. If false positive rates remain high from security scanners, add a suppression rule for known scanner user-agent strings. Increase confidence to 'high' once you have confirmed the FortiWeb version is within the affected range and have correlated network-layer detections with process-level telemetry showing shell spawning.
Hunting Queries
Threat hunting query for historical FortiWeb log review spanning 30 days, looking for HTTP requests containing OS command interpreter invocations or download utility references that may indicate successful exploitation or post-exploitation activity.
CommonSecurityLog
| where DeviceVendor =~ "Fortinet" and DeviceProduct =~ "FortiWeb"
| where TimeGenerated > ago(30d)
| where RequestURL has_any ("/bin/sh", "/bin/bash", "wget", "curl ", "nc ", "ncat", "python -c", "perl -e")
or AdditionalExtensions has "process_name=/bin/"
| summarize count() by SourceIP, RequestURL, bin(TimeGenerated, 1h)
| where count_ > 3
| sort by count_ descindex=network sourcetype=fortinet:fortiweb earliest=-30d
| where match(uri_path, "(?i)(\/bin\/sh|\/bin\/bash|wget |curl |netcat|nc |python -c|perl -e)")
OR match(msg, "(?i)(os.command|shell.exec|execve|\/bin\/sh)")
| stats count by src_ip, uri_path, msg
| where count > 2
| sort - countAtomic Red Team Tests
Simulates an OS command injection attempt against a FortiWeb management or inspection endpoint by injecting a semicolon-delimited shell command into the URI path. Lab use only.
Command
curl -sk 'https://TARGET_FORTIWEB_IP/cgi-bin/module;id;whoami' -H 'User-Agent: Mozilla/5.0' --max-time 10 -o /tmp/fortiweb_test_output.txt && cat /tmp/fortiweb_test_output.txtCleanup
rm -f /tmp/fortiweb_test_output.txtExpected Telemetry
FortiWeb access logs showing HTTP GET request to /cgi-bin/module;id;whoami from test IP. CommonSecurityLog entry with RequestURL containing semicolons.
Expected Detection
KQL and SPL queries matching on RequestURL containing ';' pattern from non-admin source IP
Tests detection of URL-encoded OS command injection payload (%3B = ';', %7C = '|') that may bypass simple string matching but should be caught by URL-decode-aware detections.
Command
curl -sk 'https://TARGET_FORTIWEB_IP/api/v1/config%3Bid%3Bwhoami' -H 'Content-Type: application/json' --max-time 10 -v 2>&1 | tee /tmp/fortiweb_encoded_test.txtCleanup
rm -f /tmp/fortiweb_encoded_test.txtExpected Telemetry
FortiWeb logs showing request URL containing %3B sequence. Network proxy or WAF logs showing URL-decoded form with semicolons.
Expected Detection
Queries matching on URL-encoded metacharacter patterns (%3B, %7C, %26%26) in RequestURL or uri_path fields
On a test Linux host representing a compromised FortiWeb, simulates an attacker spawning a shell from a web server process to validate process-lineage detections.
Command
sudo -u www-data /bin/bash -c 'id && whoami && hostname && cat /etc/passwd | head -5 && echo CVE-2025-58034-test > /tmp/fortiweb_compromise_marker.txt'Cleanup
rm -f /tmp/fortiweb_compromise_marker.txtExpected Telemetry
Process execution log showing /bin/bash spawned with parent process www-data or httpsd equivalent. File creation event for /tmp/fortiweb_compromise_marker.txt.
Expected Detection
Elastic EQL sequence detection correlating web process parent with /bin/bash child spawn. CrowdStrike ProcessRollup2 event showing shell child of web daemon.
Simulates an attacker attempting to authenticate and inject commands via FortiWeb's management API endpoint, combining credential abuse with command injection payload.
Command
curl -sk -X POST 'https://TARGET_FORTIWEB_IP/api/v2.0/cmdb/system/admin' -H 'Content-Type: application/json' -d '{"username":"admin","password":"admin$(id)"}' --max-time 10 -o /tmp/fortiweb_api_test.txt 2>&1; cat /tmp/fortiweb_api_test.txtCleanup
rm -f /tmp/fortiweb_api_test.txtExpected Telemetry
FortiWeb authentication log showing POST to management API with injection payload in password field. CommonSecurityLog DeviceAction showing authentication attempt with anomalous credential content.
Expected Detection
Detections matching on POST body containing $() subshell syntax or shell metacharacters in authentication fields