Malicious PDF — malware analysis report

Static analysis result for SHA-256 89396cf3453a9c5e…

MALICIOUS

PDF

83.1 KB Created: 2021-09-06 06:53:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c1e9bcb8c2bb1d67ee35901781d7efa2 SHA-1: 084fdfc7a9b844cd2b3c1ded87ed351f9758abcf SHA-256: 89396cf3453a9c5e4ea06d743a5f7948a56ae1c97193f72ba08c0b739717b364
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Multiple heuristics point to the PDF being a link farm, directing users to compromised or disposable hosting sites, which is a common tactic for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://nsck-cykelmotion.dk/ckfinder/userfiles/files/pefokelalonolofo.pdf In PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/64524467857.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/manefetoxil.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/jagavuz.pdfIn PDF document text
    • https://cevhertemizlik.com/userfiles/files/43852021785.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a1a346b10---lizolu.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/69957390706.pdfIn PDF document text
    • http://clinicaveterinariasangiacomo.it/userfiles/files/97238446216.pdfIn PDF document text
    • https://landbar.com/upload/files/9983997648.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/86092911074.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/2vdu5fkjm8jetk9e7oejivf73i/kepabofabukuviniwovajad.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/bopofixujusekuwigajopote.pdfIn PDF document text
    • https://begili.com/uploads/image/files/27937981048.pdfIn PDF document text
    • http://relaxzenter.com/uploads/files/33334529725.pdfIn PDF document text
    • http://innotack.com/userfiles/files/wuraletagimisixagipuvez.pdfIn PDF document text
    • http://dvg.asia/ckfinder/uploadfiles/files/55306069024.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d51c782d6---lurizaluvuwiponenikubi.pdfIn PDF document text
    • http://jp-cable.com/d/files/wujoxaniditonam.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/ff8c5049893caf0b8a68e66b945afaaf/roxuvezodupufabi.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/83524406775.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/45906727024.pdfIn PDF document text
    • http://caigeshi.com/uploadfile/file/2021052914355573499.pdfIn PDF document text
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/uf8vlv5agj4l4eqiqn8q2f3us9/9286772774.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=jazz+guitar+etudes+tab+pdfPDF link annotation
    • 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_off0000da42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA42 19576 bytes
SHA-256: 60ec796bd518b49b975761b8e2d37d68eb86e6ad67ac711212492183d0349972
font_01_sfnt_off00010d0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012524.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12524 10696 bytes
SHA-256: 0289211f9f18b963b2c60ee820b1d87ecb0b14fea6aa2b1e50e1f76e0cb5f5ea