Malicious PDF — malware analysis report

Static analysis result for SHA-256 d0f735b757cee71f…

MALICIOUS

PDF

79.5 KB Created: 2021-09-19 07:32:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4ca5dc2f7a894d79233f8e47b8e57a83 SHA-1: 0b86251a2c3c6f0290b6202122f13fbfb2564d43 SHA-256: d0f735b757cee71f7bd271f1b9ee30fafe77930864540bd81091e10ee329827e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting and employing UTM parameters, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used to redirect users to malicious websites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://inwebjor.ru/uplcv?utm_term=android+n+symbol PDF link annotation
    • http://studiocariola.com/userfiles/files/72105913870.pdfIn PDF document text
    • http://radecznica.pl/userfiles/file/ranivilezitovugum.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/podedabanumur.pdfIn PDF document text
    • https://www.sacict.or.th/ckfinder/userfiles/files/bemobexiwuwobumetaregide.pdfIn PDF document text
    • https://karaari.leaddeehub.com/userfiles/files/77862710026.pdfIn PDF document text
    • https://hocaukhudothithanhphogiaoluu.com/asset/site/files/wokojadow.pdfIn PDF document text
    • http://membranekeyboard.pl/_data/file/95367589009.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/87845763314.pdfIn PDF document text
    • http://atem.sciara.eu/public/upload/file/wumifizurexir.pdfIn PDF document text
    • http://abc-tel.ru/data/File/zosojajarigitop.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/seregofotojabegijake.pdfIn PDF document text
    • http://elitakhealing.com/ckfinder/userfiles/files/9611811590.pdfIn PDF document text
    • http://mosme.org/uploadfile/files/70512303442.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145aec1a93b9---wavaxeretepatezepi.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/zukesapimot.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/pmpcnnpl9kh6bmt001e3ig6h84/zofatetuworufafu.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/6458604833.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/84859487595.pdfIn PDF document text
    • http://choragwica.pl/userfiles/file/27002843247.pdfIn PDF document text
    • http://ranahytta.com/ckfinder/userfiles/files/xapuzuvejul.pdfIn PDF document text
    • http://giteduguedesboires.fr/userfiles/file/92041811536.pdfIn PDF document text
    • https://doosradashak.in/ci/userfiles/files/85109874303.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/nalep.pdfIn PDF document text
    • https://sanaspinler.com/calisma2/files/uploads/xuneta.pdfIn PDF document text
    • http://autosklo.sk/pictures/file/dateri.pdfIn PDF document text
    • http://remont-etalon.ru/upload/files/zojaga.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_off0000d104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD104 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e916.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE916 18612 bytes
SHA-256: c62345392898216767db78afc1eed00b9b3b4734b4bfb6430f49ec1cf1392c5d
font_02_sfnt_off0001195b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1195B 10252 bytes
SHA-256: 4947ba826e85a524cb6d7d9380d797091d2826372fce865a1bfdf8d7d93681f4