Filezilla Client do not work first 5-6 minutes after start with 100% CPU load

[User85488925]

When I start the client, one core is loaded at 100% for 5-6 minutes.
However, I can not connect to the sftp server saved in the settings. A new tab appears, but it is empty. The console is empty. The indicator does not show that some operation is occurring.
I can click refresh, but it does not give anything.
I can press interrupt the current operation, but it does not give anything.
The second tab to the same server is also empty.

If I click check for new versions, a dialog window will be displayed, there will be rotation progress bar until background load not ended.

Until the background process completes its work, the client is completely useless.

Through Process Explorer, I can look at stack on thread, which creates the download:

ntoskrnl.exe!memset+0x85f
libgnutls-30.dll!gnutls_group_get_name+0x26308
libgnutls-30.dll!gnutls_group_get_name+0x24a7d
libgnutls-30.dll!gnutls_x509_crl_import+0xa6
libgnutls-30.dll!gnutls_x509_crl_list_import+0x46
libgnutls-30.dll!gnutls_x509_crl_list_import2+0x60
libgnutls-30.dll!gnutls_x509_trust_list_add_trust_mem+0xea
libgnutls-30.dll!gnutls_x509_trust_list_add_system_trust+0x121
libfilezilla-0.dll!ZN2fz9tls_layer31generate_selfsigned_certificateERKNSt7__cxx1112basic_stringIwSt11char_traitsIwESaIwEEERKNS2_IcS3_IcESaIcEEERKSt6vectorISB_SaISB_EE+0x87ba
libfilezilla-0.dll!ZN2fzplERKNS_8durationES2_+0x13a2
libfilezilla-0.dll!ZN2fz18replace_substringsERNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEERKS5_S8_+0x14f
msvcrt.dll!srand+0x93
msvcrt.dll!ftime64_s+0x1dd
kernel32.dll!BaseThreadInitThunk+0xd
ntdll.dll!RtlUserThreadStart+0x21

If I close the client while the background task is running, the window will disappear, but the process will remain until it completes its work.

If I start the client again, it will again do something in the background for 5-6 minutes.

Judging by the line: generate_selfsigned_certificate
He is engaged in the fact that he generates some kind of certificates.

[User85488925]

Video with failed show update info

[User85488925]

If I try connect to plain FTP server it is work regardless background thread.
But any kind of SFTP server blocked by background thread and wait it end.

[User85488925]

FileZilla Client

---

Version: 3.45.1

Build information:

Compiled for: x86_64-w64-mingw32
Compiled on: x86_64-pc-linux-gnu
Build date: 2019-09-25
Compiled with: x86_64-w64-mingw32-gcc (GCC) 8.3-win32 20190406
Compiler flags: -g -O2 -Wall

Linked against:

wxWidgets: 3.0.5
SQLite: 3.29.0
GnuTLS: 3.6.9

Operating system:

Name: Windows 7 (build 7601, Service Pack 1), 64-bit edition
Version: 6.1
Platform: 64-bit system
CPU features: sse sse2 sse3 ssse3 sse4.1 sse4.2 avx aes pclmulqdq rdrnd lm
Settings dir: C:\Users\User\AppData\Roaming\FileZilla\

[Tim Kosse]

For some reason your operating system's trust store has an insurmountable amount of gigantic certificate revocation lists. CRLs need to be parsed for security reasons.

Find out why your system has such abnormally huge lists and remedy the problem.

[User85488925]

Thanks for point direction. I resolve issue via regedit.

Open
HKEY_CURRENT_USER\Software\Microsoft\SystemCertificates\CA\CRLs

I see few CRLs with not fit one blob field. It is show with subitems.
I full exported all CRLs branch to .reg file as backup.

After that remove 4 subitems which have plus on it (subitems).
One item have 250 (!) subitem blobs.

After that I run filezilla and issue gone.

Thanks for help.

PS:
Before regedit I try do clear CLRs without success via cmd line:

certutil -URLcache * delete
certutil -setreg chain\ChainCacheResyncFiletime @now

But it is not help.