Try our new Certificate Revocation List Check Tool
CRLcheck.exe is a tool developed to verify digital signatures of executable files. It collects files from known paths on your client, checks their signature, and checks Certificate Revocation Lists (CRL) and OCSP download. This helps avoid delays in launching files.

Fortigate Application Filter Certificate wrong/missing Entry sample for an important laptop driver (W10 Deployment fails because of signed Driver Revocation Lookup)

OR HOW a missing small ENTRY I a FORTIGATE FIREWALL IPS/APP filter can ruin your Windows 10 OS-Deployment work.


Reason: Missing entry in Fortigate Application Filter “ROOT.CERTIFICATE.URL” and “OCSP” source of failing deployment


Windows 10 Deployment with commercial Deployment Products (This includes HP client hardware, Microsoft SCCM, Landesk or Ivanti Frontrange).

During the Unattend phase the driver for MASS storage or NIC does a Certificate Revocation Lookup. However the as sample mentioned

URL (Hardware Driver URL, CRL FQDN) is missing in Fortiguard definitions. Thus the Fortigate does block the access to WAN. Since this is an early setup phase of W10, group Policy or special GPO do not pull at that moment.


Fortigate has already missed several PKI URL the last few months confirmed by ticket resulting in large trouble and delay on client and Server OS of customers who route their Client or Server traffic through Web proxy and because of security do not want to route computer account proxy traffic standard to the proxy.


Why this is so important. Why this is generating a lot of work and trouble for OS-Deployment teams.


The normal way in larger companies is that all outgoing traffic from client VLAN goes to Firewall which it blocks. All Web/Application/Socks traffic that should go outside goes to a Proxy, Web filter.

Because in early phase of Deployment those options are not set already and normally not needed. However if the driver is older than the Expiration of the Code Signing Certificate W7/W10 will check

The Certificate Revocation list from WAN/Internet. If that fails it may refuse to integrate the driver in Windows PE or early Windows Setup phase. If example this is a driver which

handels NIC (network) or mass Storage driver (Disk) they deployment can’t run through this early process.





URL we need open in our sample: which prevents a complete Enterprise Deployment system to fail




Sample from Fortigate for other Certs they missed:


F-SBID( –name “Root.Certificate.URL_Custom”; –protocol tcp; –app_cat 17; –service HTTP; –flow from_client; –pcre “/(crl\.microsoft\.com|\.omniroot\.com|\.verisign\.com|\.symcb\.com|\.symcd\.com|\.verisign\.ne t|\.geotrust\.com|\.entrust\.net|\.public- trust\.com|\.globalsign\.|\.digicert\.com|crl\.startcom\.|crl\.cnnic\.cn|crl\.identrust\.com|crl\.thaw te\.com|crlsl\.wosign\.com|www\.d\-trust\.net)/”; –context host; –weight 15; )


In our case:


F-SBID( –name “”; –protocol tcp; –app_cat 17; –service HTTP; — flow from_client; –pcre “/(pki\.infineon\.com)/”; –context host; –weight 15; )

Please also see: | The certificate is invalid for exchange server usage Exchange 2010 SAN/UC

So you understand that this is a problem which persists over all firewall producers:

Symantec: About the Install Readiness Check for Certificate Revocation List access

TEND MICRO: After upgrading OfficeScan, users complained that the server started to rename all files in the OfficeClient Directory to “_invalid”.
Below is a sample list of files in the D:\app\Trend Micro\OfficeScan\PCCSRV\Admin directory:


If there is no Internet connection, then CRL fetch and intermediate CA fetch will fail (this will be logged). The inspection will take place; however, URL-based or Category-based bypassing will not work.

Note: The CRL verifications are performed in the background asynchronously while matching the security policy (this mimics the behavior of the major web browsers).

Untrusted certificates and lack of CRLs can be configured as reasons to drop the connection