Detect Palo Alto Networks PAN-OS Out-of-bounds Write (CVE-2026-0300) in Microsoft Sentinel
Detects exploitation attempts targeting CVE-2026-0300, an out-of-bounds write vulnerability (CWE-787) in Palo Alto Networks PAN-OS. This vulnerability is actively exploited in the wild (CISA KEV) and may allow attackers to execute arbitrary code, crash the device, or escalate privileges on affected PAN-OS appliances. Detection focuses on anomalous management plane activity, unexpected process crashes, memory corruption indicators, and suspicious inbound traffic patterns targeting PAN-OS management interfaces.
MITRE ATT&CK
- Tactic
- Initial Access Execution Impact
KQL Detection Query
let timeframe = 24h;
let suspiciousPaths = dynamic(['/esp/', '/php/', '/sslmgr', '/global-protect', '/ssl-vpn', '/api/']);
let knownMgmtPorts = dynamic([443, 4443, 8443]);
union
(
CommonSecurityLog
| where TimeGenerated >= ago(timeframe)
| where DeviceVendor == "Palo Alto Networks"
| where Activity has_any ("threat", "vulnerability", "overflow", "memory", "crash", "segfault")
| project TimeGenerated, DeviceVendor, DeviceProduct, Activity, SourceIP, DestinationIP, DestinationPort, Message, AdditionalExtensions
),
(
AzureNetworkAnalytics_CL
| where TimeGenerated >= ago(timeframe)
| where DestPort_d in (knownMgmtPorts)
| where FlowStatus_s == "A"
| summarize RequestCount = count(), UniqueSourceIPs = dcount(SrcIP_s) by DestPublicIPs_s, DestPort_d, bin(TimeGenerated, 5m)
| where RequestCount > 500 or UniqueSourceIPs > 50
| project TimeGenerated, DestPublicIPs_s, DestPort_d, RequestCount, UniqueSourceIPs
),
(
Syslog
| where TimeGenerated >= ago(timeframe)
| where ProcessName has_any ("pan_gp", "pan_comm", "sslmgrd", "authd", "configd")
| where SyslogMessage has_any ("segfault", "core dump", "out of bounds", "memory corruption", "stack smash", "buffer overflow")
| project TimeGenerated, Computer, ProcessName, SyslogMessage
)
| extend CVE = "CVE-2026-0300"
| project-reorder TimeGenerated, CVEDetects CVE-2026-0300 exploitation indicators in Palo Alto Networks PAN-OS by correlating CommonSecurityLog threat events, anomalous inbound traffic volumes to management ports, and syslog messages indicating memory corruption or process crashes on PAN-OS devices.
Data Sources
Required Tables
False Positives & Tuning
- Legitimate vulnerability scanners (Tenable, Qualys, Rapid7) performing authorized assessments against PAN-OS management interfaces
- PAN-OS software updates or content updates that trigger brief process restarts logged as crashes
- High-volume authenticated API usage from automation platforms that may resemble volumetric anomalies
- Network monitoring tools performing continuous health checks against management ports
Other platforms for CVE-2026-0300
Testing Methodology
Validate this detection against 3 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 1Simulate malformed HTTPS payload to PAN-OS management interface
Expected signal: PAN-OS threat logs should record an anomalous inbound connection; syslog may show a connection handling error or rate limit trigger on the management interface.
- Test 2Trigger PAN-OS management daemon crash simulation via process kill
Expected signal: PAN-OS system logs will record a process crash event for sslmgrd with signal 11 (SIGSEGV); watchdog restart will generate a subsequent SYSTEM log entry. Syslog forwarding will push these to the SIEM.
- Test 3Enumerate PAN-OS management interface exposure and version fingerprinting
Expected signal: PAN-OS management logs will record the inbound HTTPS requests from the test source IP. If threat prevention is enabled, reconnaissance-pattern requests may trigger a threat log entry.
Unlock Pro Content
Get the full detection package for CVE-2026-0300 including response playbook, investigation guide, and atomic red team tests.