Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9934f03c4a6e273…

MALICIOUS

PDF

75.1 KB Created: 2021-09-13 16:50:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 06b1797914abfb180523d08968b8c663 SHA-1: 946126f6d2e1c3c0f063051dc4028c32215a7f44 SHA-256: a9934f03c4a6e273e2c73358926b40c4d147542c0233c13cbfea1cb1d36046e5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are structured as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of UTM parameters in one URL suggest a phishing or malicious redirection attempt. ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://infrive.ru/uplcv?utm_term=unchecked+discord+nitro+codes PDF link annotation
    • http://zoldjogsi.hu/uploads/files/wubovovowonuludo.pdfIn PDF document text
    • https://momentous-inst.com/uploads/image/files/mukezo.pdfIn PDF document text
    • https://angkalaris.com/contents/files/69384953203.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/92284189128.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e21fdbd05b---fujegepefu.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/161372ad06e228---torokozolusawaxudizuxopu.pdfIn PDF document text
    • http://corse.annuaire-regional.com/ckfinder/userfiles/files/kogowewuzuboduzadunu.pdfIn PDF document text
    • http://babamoleskine.com/files/file/53591703379.pdfIn PDF document text
    • http://ltptech.vn/uploads/userfiles/file/mutanuwabuzoremidawijuzut.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210905_5ECFFC8FA082AD8B.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/4134215653.pdfIn PDF document text
    • https://www.htlexpress.com/ckfinder/userfiles/files/10959541187.pdfIn PDF document text
    • https://signatureshreyas.in/userfiles/file/41710890571.pdfIn PDF document text
    • https://navoloki.mebel18.com/uploads/files/vawumefaxezolimobegeka.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/mofamawolowagirakipa.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/bomoxesidagow.pdfIn PDF document text
    • https://magnanerie-cazilhac.com/userfiles/file/sezizafotulotosinakiga.pdfIn PDF document text
    • http://chulatutoracademy.com/chulatutor/ckfinder/userfiles/files/8514441326.pdfIn PDF document text
    • https://windfreeklima.com/upload/ckfinder/files/lesapozijunage.pdfIn PDF document text
    • http://giaodantanthaison.com/Images_upload/files/zoxinusijixufadipud.pdfIn PDF document text
    • http://uzks.hr/upload/datoteke/gexelotopufebozazej.pdfIn PDF document text
    • https://myarchitect.es/ckfinder/userfiles/files/dipeditetufafukap.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/33931710668.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c254.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC254 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA66 17272 bytes
SHA-256: 6320b469f1e9a0175dcb66ddf8a0408d84cbee8a2eac98261db217a35ba903bf
font_02_sfnt_off000106e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E4 10360 bytes
SHA-256: 6ceff0ff6885e4f82bdab46ffcb577c5ee37fecbfc370703505a34773e636ad1