Malicious PDF — malware analysis report

Static analysis result for SHA-256 677819bfe9fec7b4…

MALICIOUS

PDF

74.7 KB Created: 2021-09-17 15:13:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c8dc1fc97cfb93764c254aefc3823fa9 SHA-1: 0840f54710b880c662c10b1c8eea06cba220eea0 SHA-256: 677819bfe9fec7b46f122f5df2fdbb4ebb838f05e00942781a6d8ded636b9987
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous URLs, many of which point to compromised or disposable hosting. Heuristics indicate a link farm designed to direct users to external sites, consistent with phishing or malware distribution tactics. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://www.jokilaaksonratsastajat.fi/file/91607000656.pdf
    • https://baxsporthorses.nl/userfiles/file/32591649364.pdf
    • http://masonhn.com/d/files/42947131072.pdf
    • http://everbeenmagnet.com/js/upfiles/files/wijirevirep.pdf
    • http://zabbeleecooking.com/ckfinder/userfiles/files/89140825033.pdf
    • http://namadagaskare.ru/ckfinder/userfiles/files/84517991131.pdf
    • https://www.barefoothoa.com/webroot/js/ckfinder/userfiles/files/dejebak.pdf
    • https://leresto-niort.fr/images/userfiles/files/1586970178.pdf
    • http://aalzkj.love-mrt.com/upload/files/56873703725.pdf
    • https://cfi-registration.org/buzzboxgift/img/userfiles/files/xaliposelebefigaduviki.pdf
    • http://smartvoicecom.com/userfiles/53504059824.pdf
    • http://cortocircuito.trialpanel.com/images/Upload/files/12702637735.pdf
    • http://stringquartet.biz/web/images/fck/file/12729265377.pdf
    • http://industrialsupplies.pk/userfiles/files/99158105752.pdf
    • http://montpellier-businessplan.com/mbp/upload/images/images/upload/ckfinder/36553030451.pdf
    • https://seger.cz/userfiles/file/1965067870.pdf
    • https://vicotelecom.vn/static/source/images/file/53197425029.pdf
    • http://zezoalza.com/ckupload/files/80683545300.pdf
    • https://wisserarm.nl/app/webroot/files/userfiles/files/lefomisifijinup.pdf
    • https://pielinks.com/UserFiles/file/degebatoge.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/0d245002b0e471e9718cf09e2971ebb4/4267044125.pdf
    • https://pierreseche.fr/userfiles/file/25790957669.pdf
    • http://tunecharts.com/userfiles/file/wowamufele.pdf
    • http://notariocprietoa.com/notaria/documentos/files/66513470989.pdf
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/pnhiidph7922068te2tgo6iv47/85951588151.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138b35a2f212---nasufumeterelaziredowaz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=how+to+stop+play+store+update
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c1e2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC1E2 16792 bytes
font_01_sfnt_off0000d9f9.bin
9b8d8264d81eb8a352ca08719f5c7ff081ca90909525fa6caae64f245612efc3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F9 10480 bytes
font_02_sfnt_off0000f205.bin
a5f864690049c81d0285fa9b5b49061514767730e271f2782812731508ad8152
pdf-font-stream PDF embedded font (sfnt) at offset 0xF205 16784 bytes