rkhunter update failed, cannot find dat files

I have a CentOs 7.6 up and running with rkhunter for a long time now. After all my os updates, I run rkhunter --update --propupd but it fails since recently.

[ Rootkit Hunter version 1.4.6 ]
File updated: searched for 175 files, found 133

Checking rkhunter data files...
  Checking file mirrors.dat                                  [ Update failed ]
  Checking file programs_bad.dat                             [ Update failed ]
  Checking file backdoorports.dat                            [ Update failed ]
  Checking file suspscan.dat                                 [ Update failed ]
  Checking file i18n versions                                [ Update failed ]

Please check the log file (/var/log/rkhunter/rkhunter.log)

[15:21:15] Running Rootkit Hunter version 1.4.6 on stadler-jonas
[15:21:15]
[15:21:15] Info: Start date is Mon 29 Mar 15:21:15 CEST 2021
[15:21:15]
[15:21:15] Checking configuration file and command-line options...
[15:21:15] Info: Detected operating system is 'Linux'
[15:21:15] Info: Found O/S name: CentOS Linux release 7.9.2009 (Core)
[15:21:16] Info: Command line is /bin/rkhunter --update --propupd
[15:21:16] Info: Environment shell is /bin/zsh; rkhunter is using bash
[15:21:16] Info: Using configuration file '/etc/rkhunter.conf'
[15:21:16] Info: Installation directory is '/usr'
[15:21:16] Info: Using language 'en'
[15:21:16] Info: Using '/var/lib/rkhunter/db' as the database directory
[15:21:16] Info: Using '/usr/share/rkhunter/scripts' as the support script directory
[15:21:16] Info: Using '/usr/local/sbin /usr/local/bin /sbin /bin /usr/sbin /usr/bin /usr/libexec /usr/local/libexec' as the command directories
[15:21:16] Info: Using '/var/lib/rkhunter' as the temporary directory
[15:21:16] Info: X will be automatically detected
[15:21:16] Info: Found the 'basename' command: /bin/basename
[15:21:16] Info: Found the 'diff' command: /bin/diff
[15:21:16] Info: Found the 'dirname' command: /bin/dirname
[15:21:16] Info: Found the 'file' command: /bin/file
[15:21:16] Info: Found the 'find' command: /bin/find
[15:21:16] Info: Found the 'ifconfig' command: /sbin/ifconfig
[15:21:16] Info: Found the 'ip' command: /sbin/ip
[15:21:16] Info: Found the 'ipcs' command: /bin/ipcs
[15:21:16] Info: Found the 'ldd' command: /bin/ldd
[15:21:16] Info: Found the 'lsattr' command: /bin/lsattr
[15:21:16] Info: Found the 'lsmod' command: /sbin/lsmod
[15:21:16] Info: Found the 'lsof' command: /sbin/lsof
[15:21:16] Info: Found the 'mktemp' command: /bin/mktemp
[15:21:16] Info: Found the 'netstat' command: /bin/netstat
[15:21:16] Info: Found the 'numfmt' command: /bin/numfmt
[15:21:16] Info: Found the 'perl' command: /bin/perl
[15:21:16] Info: Found the 'pgrep' command: /bin/pgrep
[15:21:16] Info: Found the 'ps' command: /bin/ps
[15:21:16] Info: Found the 'pwd' command: /bin/pwd
[15:21:16] Info: Found the 'readlink' command: /bin/readlink
[15:21:16] Info: Found the 'stat' command: /bin/stat
[15:21:16] Info: Found the 'strings' command: /bin/strings
[15:21:16] Info: Found the 'wget' command: /bin/wget
[15:21:16] Info: System is not using prelinking
[15:21:16] Info: Using the '/bin/sha256sum' command for the file hash checks
[15:21:16] Info: Stored hash values used hash function '/bin/sha256sum'
[15:21:16] Info: Stored hash values used package manager 'RPM'
[15:21:17] Info: The hash function field index is set to 1
[15:21:17] Info: Using package manager 'RPM' to update the file hash values
[15:21:17] Info: Found the 'rpm' command: /bin/rpm
[15:21:17] Info: Using package manager 'RPM' for file property checks
[15:21:17] Info: Found the 'rpm' command: /bin/rpm
[15:21:17] Info: Current file attributes will be stored
[15:21:17] Info: The mirrors file will be rotated
[15:21:17] Info: Both local and remote mirrors will be used
[15:21:17] Info: The mirrors file will be updated
[15:21:17] Info: Logging to log file: /var/log/rkhunter/rkhunter.log
[15:21:17] Info: Current logging will be appended to the log file
[15:21:17] Info: Locking is not being used
[15:21:17]
[15:21:17] Info: Starting file properties data update...
[15:21:17] Info: Created temporary file '/var/lib/rkhunter/rkhunter.dat.kQfKgSvfuC'
[15:21:17] Collecting O/S info...
[15:21:17] Info: Found system architecture: x86_64
[15:21:17] Info: Found release file: /etc/system-release
[15:21:17] Info: Found O/S name: CentOS Linux release 7.9.2009 (Core)
[15:21:17] Getting file properties...
[15:21:52] Info: Found 35 files in /usr/sbin
[15:21:52] Info: Found 97 files in /usr/bin
[15:21:52] Info: Found 1 files in /usr/lib/systemd
[15:21:52] Info: File updated: searched for 175 files, found 133
[15:21:52] Info: New 'rkhunter.dat' file installed in '/var/lib/rkhunter/db'
[15:21:52]
[15:21:52] Checking rkhunter data files...
[15:21:52] Info: Created temporary file '/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv'
[15:21:52] Info: Created temporary file '/var/lib/rkhunter/mirrors.dat.wwO4z9hT3K'
[15:21:52] Info: The mirrors file has been rotated: /var/lib/rkhunter/db/mirrors.dat
[15:21:52] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/mirrors.dat 2>/dev/null'
[15:21:53] Info: Download failed - 1 mirror(s) left.
[15:21:53] Info: Created temporary file '/var/lib/rkhunter/mirrors.dat.sknQKrCqq0'
[15:21:53] Info: The mirrors file has been rotated: /var/lib/rkhunter/db/mirrors.dat
[15:21:53] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/mirrors.dat 2>/dev/null'
[15:21:54] Warning: Download of 'mirrors.dat' failed: Unable to determine the latest version number.
[15:21:54] Checking file mirrors.dat                         [ Update failed ]
[15:21:54] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/programs_bad.dat 2>/dev/null'
[15:21:56] Info: Download failed - 1 mirror(s) left.
[15:21:56] Info: Created temporary file '/var/lib/rkhunter/mirrors.dat.NmhUHcrnHM'
[15:21:56] Info: The mirrors file has been rotated: /var/lib/rkhunter/db/mirrors.dat
[15:21:56] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/programs_bad.dat 2>/dev/null'
[15:21:57] Warning: Download of 'programs_bad.dat' failed: Unable to determine the latest version number.
[15:21:57] Checking file programs_bad.dat                    [ Update failed ]
[15:21:57] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/backdoorports.dat 2>/dev/null'
[15:21:58] Info: Download failed - 1 mirror(s) left.
[15:21:58] Info: Created temporary file '/var/lib/rkhunter/mirrors.dat.3ROpkzWzsB'
[15:21:58] Info: The mirrors file has been rotated: /var/lib/rkhunter/db/mirrors.dat
[15:21:58] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/backdoorports.dat 2>/dev/null'
[15:21:59] Warning: Download of 'backdoorports.dat' failed: Unable to determine the latest version number.
[15:21:59] Checking file backdoorports.dat                   [ Update failed ]
[15:21:59] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/suspscan.dat 2>/dev/null'
[15:22:00] Info: Download failed - 1 mirror(s) left.
[15:22:00] Info: Created temporary file '/var/lib/rkhunter/mirrors.dat.h8e1l69V8g'
[15:22:01] Info: The mirrors file has been rotated: /var/lib/rkhunter/db/mirrors.dat
[15:22:01] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/suspscan.dat 2>/dev/null'
[15:22:02] Warning: Download of 'suspscan.dat' failed: Unable to determine the latest version number.
[15:22:02] Checking file suspscan.dat                        [ Update failed ]
[15:22:02] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/i18n/1.4.6/i18n.ver 2>/dev/null'
[15:22:03] Info: Download failed - 1 mirror(s) left.
[15:22:03] Info: Created temporary file '/var/lib/rkhunter/mirrors.dat.qXcc7W49IK'
[15:22:03] Info: The mirrors file has been rotated: /var/lib/rkhunter/db/mirrors.dat
[15:22:03] Info: Executing download command '/bin/wget  -q -O "/var/lib/rkhunter/rkhunter.upd.6SWKSwOOqv" https://rkhunter.sourceforge.io/i18n/1.4.6/i18n.ver 2>/dev/null'
[15:22:04] Checking file i18n versions                       [ Update failed ]
[15:22:04] Warning: Download of 'i18n.ver' failed: Unable to determine the latest version number.
[15:22:04]
[15:22:04] Info: End date is Mon 29 Mar 15:22:04 CEST 2021

When I try to open one of the .dat files in my browser (http://rkhunter.sourceforge.net/mirrors.dat) I get the following:

An error has been encountered in accessing this page.

1. Server: rkhunter.sourceforge.net
2. URL path: /mirrors.dat
3. Error notes: NONE
4. Error type: 404
5. Request method: GET
6. Request query string: NONE
7. Time: 2021-03-29 13:22:53 UTC (1617024173)

Reporting this problem: The problem you have encountered is with a project web site hosted by SourceForge.net. This issue should be reported to the SourceForge.net-hosted project (not to SourceForge.net).

If this is a severe or recurring/persistent problem, please do one of the following, and provide the error text (numbered 1 through 7, above):

Contact the project via their designated support resources.
Contact the project administrators of this project via email (see the upper right-hand corner of the Project Summary page for their usernames) at [email protected]
If you are a maintainer of this web content, please refer to the Site Documentation regarding web services for further assistance.

NOTE: As of 2008-10-23 directory index display has been disabled by default. This option may be re-enabled by the project by placing a file with the name ".htaccess" with this line:

Options +Indexes

I googled a lot, but cannot find something of great help.

Please check the content of /var/lib/rkhunter/db/mirrors.dat. If the content is

Version:2021020601
remote=https://rkhunter.sourceforge.io
mirror=https://rkhunter.sourceforge.io

change it to

Version:2021020602
mirror=http://rkhunter.sourceforge.net
remote=http://rkhunter.sourceforge.net

Also check your MIRRORS_MODE configuration (in /etc/rkhunter.conf). In most cases this value should be set to 0

Look also at:

• https://sourceforge.net/p/rkhunter/mailman/rkhunter-users/thread/87af14dae764b704d5302030f92b3160%40192.168.1.2/#msg37313895
• https://sourceforge.net/p/rkhunter/mailman/message/37214275/