Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b87a9fcf00a1e2…

MALICIOUS

PDF

68.4 KB Created: 2021-10-01 16:14:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 9cc0aeeca7337d1b7ca02fbd61cf2ef4 SHA-1: 330624f8b55b7c47eaf36ac64a6ac64bf1cba924 SHA-256: 77b87a9fcf00a1e248206bc420178865d4eb394acefbb16e39710126db0831bf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is flagged as a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure itself facilitates the redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://cructi.ru/uplcv?utm_term=i+recorder+apk PDF link annotation
    • http://fizjoactiv.eu/Upload/file/34490758911.pdfIn PDF document text
    • https://ihotel2b.com/upfiles/editor/files/16952647636.pdfIn PDF document text
    • http://gamax-moto.cz/data/dokumenty/64953687969.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/78101481657.pdfIn PDF document text
    • https://elminhaj.org/userfiles/file/ditevoredobadofe.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/siwubuxedasenalineze.pdfIn PDF document text
    • https://efnnma.org/files/file/sukoxupamokagawu.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/bf944da3b7f6776f898b50fbec6637d7/77771117823.pdfIn PDF document text
    • https://mimpidia2.com/contents/files/60822719705.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/38501631777.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/15790067142.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6bba5bf29---81267615471.pdfIn PDF document text
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/zofoxenozerikor.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/gepivizuvuserudu.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/82074799136.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/sawijofe.pdfIn PDF document text
    • http://studio70.eu/userfiles/files/terinopexunenewaxesuv.pdfIn PDF document text
    • https://pcetravel.com/files/file/xigefux.pdfIn PDF document text
    • http://lammensfilip.be/uploads/files/jobanotumumezudobinefesij.pdfIn PDF document text
    • http://klimatyzacjaradom.pl/userfiles/file/wujaderabodazogafudejatu.pdfIn PDF document text
    • http://mopron.ru/upload/files/7765736648.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/2634870826.pdfIn PDF document text
    • http://deliver.cueicha.com/assets/upload/files/fexedopilu.pdfIn PDF document text
    • http://jtour.vn/userfiles/file/govajisobunedurafifuxazij.pdfIn PDF document text
    • http://tongshengchem.com/ckfinder/userfiles/files/doxasogafagonuzifik.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_off0000af5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF5A 15288 bytes
SHA-256: 1c5661b4b58386c066eab473def3cfa209e48ef4cc0977e95c1f41e61f9a2a28
font_01_sfnt_off0000d608.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD608 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1F 10040 bytes
SHA-256: 9e3c5bf1f186d8a509943bd69decd03ed6ccfa85a3c94cdff99010862d604612