[clamav-users] signature exists, but not detecting

[Al Varnell]

On Tue, Feb 23, 2021 at 09:30 AM, Ron Seguin via clamav-users wrote:
> Hi,
> 
> Uploaded a file to virustools.com <http://virustools.com/> and results show that ClamAV detects the Unix.Trojan.Tsunami-6981155-0 exploit. 

I'm not familiar with virustools.com and I get a redirect when I attempt to access it. Did you mean VirusTotal? If so, can you provide the link to the actual results of the file you uploaded?

> The command-line utility did not detect it.  Up-to-date DB.  The signature appears to exist in the signature database.
> 
> Something I'm missing?
> 
> # freshclam
> ClamAV update process started at Tue Feb 23 12:12:30 2021
> daily.cld database is up to date (version: 26089, sigs: 4000162, f-level: 63, builder: raynman)
> main.cvd database is up to date (version: 59, sigs: 4564902, f-level: 60, builder: sigmgr)
> bytecode.cvd database is up to date (version: 332, sigs: 93, f-level: 63, builder: awillia2)
> 
> 
> # clamscan /var/tmp/pty3
> /var/tmp/pty3: OK
> ----------- SCAN SUMMARY -----------
> Known viruses: 8565230
> Engine version: 0.103.1
> Scanned directories: 0
> Scanned files: 1
> Infected files: 0
> Data scanned: 0.04 MB
> Data read: 0.04 MB (ratio 1.00:1)
> Time: 14.528 sec (0 m 14 s)
> Start Date: 2021:02:23 12:13:43
> End Date:   2021:02:23 12:13:57
> 
> 
> # sigtools --find "6981155"
> [daily.ldb] Unix.Trojan.Tsunami-6981155-0;Engine:51-255,Target:6;0&1&2&3&4;4d6f7a696c6c612f342e302028636f6d70617469626c653b204d53494520372e303b2057696e646f7773204e5420362e303b204d794945323b20534c4343313b202e4e455420434c5220322e302e35303732373b204d656469612043656e74657220504320352e3029;4d6f7a696c6c612f352e30202857696e646f77733b20553b2057696e646f7773204e5420362e313b2063733b2072763a312e392e322e3629204765636b6f2f3230313030363238206d796962726f772f34616c70686132;4d6f7a696c6c612f352e302028636f6d70617469626c653b20553b204142726f77736520302e363b2053796c6c61626c6529204170706c655765624b69742f3432302b20284b48544d4c2c206c696b65204765636b6f29;4d6f7a696c6c612f352e3020285831313b20553b204c696e757820693638363b20706c2d504c3b2072763a312e392e302e3629204765636b6f2f32303039303230393131;4d6f7a696c6c612f352e3020284d6163696e746f73683b20553b20496e74656c204d6163204f5320583b20656e3b2072763a312e382e312e313129204765636b6f2f32303037313132382043616d696e6f2f312e352e34

You might find this breakout more useful when searching the file for matching strings:

~ % sigtool -fUnix.Trojan.Tsunami-6981155-0|sigtool --decode-sigs 
VIRUS NAME: Unix.Trojan.Tsunami-6981155-0
TDB: Engine:51-255,Target:6
LOGICAL EXPRESSION: 0&1&2&3&4
 * SUBSIG ID 0
 +-> OFFSET: ANY
 +-> SIGMOD: NONE
 +-> DECODED SUBSIGNATURE:
Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; MyIE2; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0)
 * SUBSIG ID 1
 +-> OFFSET: ANY
 +-> SIGMOD: NONE
 +-> DECODED SUBSIGNATURE:
Mozilla/5.0 (Windows; U; Windows NT 6.1; cs; rv:1.9.2.6) Gecko/20100628 myibrow/4alpha2
 * SUBSIG ID 2
 +-> OFFSET: ANY
 +-> SIGMOD: NONE
 +-> DECODED SUBSIGNATURE:
Mozilla/5.0 (compatible; U; ABrowse 0.6; Syllable) AppleWebKit/420+ (KHTML, like Gecko)
 * SUBSIG ID 3
 +-> OFFSET: ANY
 +-> SIGMOD: NONE
 +-> DECODED SUBSIGNATURE:
Mozilla/5.0 (X11; U; Linux i686; pl-PL; rv:1.9.0.6) Gecko/2009020911
 * SUBSIG ID 4
 +-> OFFSET: ANY
 +-> SIGMOD: NONE
 +-> DECODED SUBSIGNATURE:
Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en; rv:1.8.1.11) Gecko/20071128 Camino/1.5.4

-Al-
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.clamav.net/pipermail/clamav-users/attachments/20210223/547ca751/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4376 bytes
Desc: not available
URL: <https://lists.clamav.net/pipermail/clamav-users/attachments/20210223/547ca751/attachment.bin>