Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac98dda4fd5089c5…

MALICIOUS

PDF

99.3 KB Created: 2021-10-04 17:10:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9073c0dfcbac19ef07034e8305e91c74 SHA-1: fb11f09e17be4324efe791b00d8d7ac505dbc552 SHA-256: ac98dda4fd5089c5997578b9e3ac6bc931359471d62f35edd6591959e5c77424
126 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. It contains numerous external URLs, many pointing to disposable hosting, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior. While no scripts were explicitly extracted, the PDF format often leverages JavaScript for malicious actions, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://allytemp.ru/uplcv?utm_term=types+of+sovereignty+in+political+science PDF link annotation
    • http://softtox.com/new/userfiles/file/72680571411.pdfIn PDF document text
    • http://jfhcoaching.com/userfiles/files/5408649640.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/tufiruzukolojabijuvinuzo.pdfIn PDF document text
    • http://xyr59.com/filespath/files/20211003180328.pdfIn PDF document text
    • http://maidichike.com/upload/files/teganalik.pdfIn PDF document text
    • https://www.cygnusdvlp.in/nitdurgapur/uploads/editorUploads/userfiles/files/xijiwasosiwigak.pdfIn PDF document text
    • http://sitarofindiamd.com/userfiles/file/dalexoxojetukeb.pdfIn PDF document text
    • http://rana-international.com/userfiles/files/kojamekuware.pdfIn PDF document text
    • https://tarzminder.com/resimler/files/fepekusiloraduzil.pdfIn PDF document text
    • https://royal-art.pl/uploads/userfiles/files/ruwujugugire.pdfIn PDF document text
    • http://heryeryesil.com/resimlerfiles/pitasaxep.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/kesojebuvizew.pdfIn PDF document text
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/18206607758.pdfIn PDF document text
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/20982282258.pdfIn PDF document text
    • http://zeci.nl/im/image/85253842423.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614095d929e22---42409543405.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/43659503498.pdfIn PDF document text
    • http://malir-naterac.info/UserFiles/File/koxigifotukejixumu.pdfIn PDF document text
    • https://sistemagestiondpr.co/userfiles/file/49874899074.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/9383080154.pdfIn PDF document text
    • http://kamkmori.cz/ckfinder/userfiles/files/kojas.pdfIn PDF document text
    • http://oldadmin.k12cart.com/media/files/39191351492.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16139e6af36427---79217601978.pdfIn PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/keraxobaxudotafefomu.pdfIn PDF document text
    • https://varbackaforskola.se/ckfinder/userfiles/files/21682646059.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c156a0883---sinejojobisibuk.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_off00011ae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000132fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132FB 10800 bytes
SHA-256: 1e76fb19cc10960e5b14b2d8a0b969ca172d5a3459522b61d3760736414ced77
font_02_sfnt_off00014c14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C14 19676 bytes
SHA-256: 792b31a0ff32a34c6d5f8b880bbd73d0a2f6897546cc900610fc035a47df5b09