NSCP.exe crashes when setting a custom payload length

[kees-z]

Issue and Steps to Reproduce

• Install latest (0.6.0.1) NSClient version
• Increase payload length by adding payload length=8192 to section [/settings/NRPE/server] in nsclient.ini.
• When using check_nrpe with NRPE v3 on the monitoring server (Icinga2), the NSCP.exe process crashes after some time (15-60 minutes).

Expected Behavior

The NSClient++ service should not stop unexpectedly when using NRPE v3.

Actual Behavior

For a short time, everything works fine, but after 15-60 minutes the NSClient++ service stops unexpectedly. Application Event log:

Log Name: Application
Source: Application Error
Event ID: 1000
Level: Error

Faulting application name: nscp.exe, version: 0.6.0.1, time stamp: 0x6596493b
Faulting module name: VCRUNTIME140.dll, version: 14.40.33810.0, time stamp: 0x5d30eadf
Exception code: 0xc0000005
Fault offset: 0x000000000000122e
Faulting process id: 0x1c50
Faulting application start time: 0x01dacc73608adbe2
Faulting application path: C:\Program Files\NSClient++\nscp.exe
Faulting module path: C:\Windows\SYSTEM32\VCRUNTIME140.dll
Report Id: 67471c36-a3c1-440f-8fcb-51acc8e4761d
Faulting package full name: 
Faulting package-relative application ID: 

Details

• NSClient++ version: 0.6.0.1
• OS and Version: Different Windows Servers versions (2012R2 up to 2022)
• Checking from: Icinga2
• Checking with: check_nrpe

Additional Details

When removing payload length=8192 from nsclient.ini and adding -2 to the check_nrpe command (forcing Icinga to use NRPE v2), the NSClient++ service runs stable. Tried it using various VC Runtime versions, all with the same result.