Malicious PDF — malware analysis report

Static analysis result for SHA-256 f18c5002175729b0…

MALICIOUS

PDF

83.0 KB Created: 2021-10-13 17:17:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 73717069b5f4f3db36b053e58a1c9294 SHA-1: 01f8019c05fe7cb6bbcd253b4588114ebf780fdf SHA-256: f18c5002175729b02db1fc50f81e507b50a55e71ac455786ad90b3526f6683ac
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs and the PDF structure suggest an attempt to redirect users to malicious sites, likely for phishing or malware delivery. No scripts were extracted, but the PDF's nature points towards social engineering tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=what+do+i+need+for+6th+grade PDF link annotation
    • http://olsztyntransportmedyczny.pl/userfiles/file/70193653116.pdfIn PDF document text
    • https://istanajp.net/contents/files/ditonegetivimasa.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/25228972137.pdfIn PDF document text
    • http://soncongnghiepjotun.com/media/ftp/file/zonovadopesorudiziwibu.pdfIn PDF document text
    • http://robvancampen.nl/userfiles/file/9395658614.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/bafodovosagotiseza.pdfIn PDF document text
    • http://thekitchendesignstudio.org/uploads/files/60865565060.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/sulijigenav.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/78547735466.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/48300607609.pdfIn PDF document text
    • http://phukientubepxinh.info/gomsu/sanpham/anh/files/76201288216.pdfIn PDF document text
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/77237875083.pdfIn PDF document text
    • https://ibshospitals.com/userfiles/file/difagumirogokipoku.pdfIn PDF document text
    • http://www.culturehousesun.org/photos/file/vamiwosevawikeji.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/mikifupel.pdfIn PDF document text
    • http://grafitym.kz/files/file/sidorigijekexovupa.pdfIn PDF document text
    • http://tianfonmm.com/d/files/52698688950.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133972ce9417---saporunugenugubiwolapuge.pdfIn PDF document text
    • http://sanraimundo.cl/dyn/uploads/file/82884736479.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/48922896987.pdfIn PDF document text
    • http://knupress.com/pds/editor/file/79311044261.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/17419097824.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-13/20210913080207170597.pdfIn PDF document text
    • https://www.caissedesecolesdu5eme.fr/backoffice/ckfinder/userfiles/files/37689736039.pdfIn PDF document text
    • http://dentalcenterstudio.it/userfiles/files/59247729733.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_off0000e16f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f981.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF981 17384 bytes
SHA-256: 99cc338b637208f7a55ffb6806cd79e2be0fcf2936934edaf71d9561cb65460b
font_02_sfnt_off000126f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126F0 10580 bytes
SHA-256: d1d4e0438bc8ce2d645fe1b1249340c9a9b0ada353334a48dfbb1143820afe2c