amavisd and centos8 compatibility

[Engels, Jan]

Hi Ralph,

yes, the tools on a particular platform are independent of amavis but
unfortunately I am currently also experiencing Problems with unrar and Amavis and in
this case it seems that the problem lies on amavis side. I was running an older version
of unrar (unrar-4.2.4-1.el7.x86_64) until a malware went through our system because the
RARv5 archive containing the malware could not be unpacked. So I've tried to upgrade the
unrar version in our systems in order to handle RARv5 archives. The problem is that after
upgrading (to unrar-5.4.0-1.el7.x86_64) I am now getting another error, such as:

amavis[21724]: (21724-01) (!)do_unrar: can't parse info line for ""  -rw-r--r--        68        72 105%  2020-04-15 15:01  6851CF3C  eicar.com\n 


I get this error when sending a test rar archive  (created by me on my ubuntu 16.04 desktop
using rar version 2:5.3.b2-1) and which only contains the typical "eicar.com" testfile. I've
confirmed that the rar archive is OK and I could even successfully unpack it on the command
line directly on my amavis machine. Here is the output:

unrar x eicar.com.rar 

UNRAR 5.40 freeware      Copyright (c) 1993-2016 Alexander Roshal


Extracting from eicar.com.rar

Extracting  eicar.com                                                 OK 
All OK



However if I send this rar archive through amavis it fails with the error shown above.

The amavis version running in our system is:
amavisd-new-2.11.1-1.el7.noarch
clamav-0.102.2-4.el7.x86_64


If I downgrade the unrar version to the previous version:
unrar-4.2.4-1.el7.x86_64

Than the test rar archive is unpacked correctly by amavis and the EICAR test is recognized:



You can For details you can check my email sent to this mailing list on 25th Mar. with subject:
"malware went through because RAR file fails to unpack".



----- Original Message -----
| From: "Ralph Seichter" <abbot at monksofcool.net>
| To: amavis-users at amavis.org
| Sent: Thursday, April 9, 2020 10:08:16 PM
| Subject: Re: amavisd and centos8 compatibility

| * support at mmarzouki.de:
| 
|> tools like unrar or cabextract is not available in centos8 with
|> epel-release and enabled PowerTools.
| 
| Amavis searches the system it is running on for some well-known
| binaries. If CentOS uses different ones, you can manually change the
| list of binaries by modifying your amavisd.conf. Also, if you don't
| expect to receive .zoo or .cab archives, not having extractor utilities
| for them won't hurt much.
| 
| What tools are available on a particular platform is not an Amavis
| issue, so I suggest you contact the CentOS package maintainers.
| 
| -Ralph