Malicious PDF — malware analysis report

Static analysis result for SHA-256 3571ad35628709b3…

MALICIOUS

PDF

82.6 KB Created: 2021-09-16 04:06:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6f051097f69c131bd8753b339b36f7a0 SHA-1: 4f0fab5de342a0cf3f47d821726380f829995dbf SHA-256: 3571ad35628709b3ea725b9afdb456df159706927b319a77455891c79dfa27d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, forming a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • 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.
  • 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://allytemp.ru/uplcv?utm_term=best+dialer+apps+for+android PDF link annotation
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161372aa38c29a---30230251043.pdfIn PDF document text
    • https://www.greenlakecruises.com/ckfinder/userfiles/files/58841696985.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/257a52a6f1f4f98c0cb36f91567b6448/84107893393.pdfIn PDF document text
    • http://unewstoday.com/task/userimages/file/71291919010.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/50275325165.pdfIn PDF document text
    • https://icnj.net/ckeditor/ckfinder/userfiles/files/98334656346.pdfIn PDF document text
    • https://hiroyoung.com/data/files/61494609298.pdfIn PDF document text
    • https://sindonis.com/userfiles/file/bufatesit.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/748a46118a00ac9f8f06e9f80439ec02/50358057156.pdfIn PDF document text
    • https://samuelben-horin.com/userfiles/file/46128506205.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/8242305629.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/10893206546.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/falitab.pdfIn PDF document text
    • https://htchninc.com/d/files/senofalojifaril.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/9154622713.pdfIn PDF document text
    • http://druckmaschinenservice.com/uploads/fce/files/82307244375.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/jasurinuxekapozuvaja.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/20935833123.pdfIn PDF document text
    • http://www.biogreeno.com/cms/ckfinder/userfiles/files/89941876109.pdfIn PDF document text
    • http://bibikid.ru/upload/76054011260.pdfIn PDF document text
    • http://aviatroglo.fr/IMG/file/30598257511.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/28349598899.pdfIn PDF document text
    • http://opakowania-loga.pl/zdjecia/fotki/file/fezuvedubutarifule.pdfIn PDF document text
    • http://yujinpharma.com/upload/files/ditifenegurinibugamage.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/46382331662.pdfIn PDF document text
    • https://rt9.rspo.org/ckfinder/userfiles/files/zubifuraroxofomaxita.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_off0000e021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE021 17320 bytes
SHA-256: fcac3cde043cded3b671b5bab17ac0dbaa48ac0e3e90215f45199c22c7da0312
font_01_sfnt_off00010c56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001246d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1246D 10544 bytes
SHA-256: c4063e6c0e682bdfd2ae9a5250cff16192f101cf2f6080983efa3b77a43f001f