Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0fdf799d624fd60…

MALICIOUS

PDF

83.3 KB Created: 2021-09-18 18:31:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6c80a076476be8ecbdb7eb13bce8aa48 SHA-1: 2e3050261af1312925af2952b0bb95204c93fe50 SHA-256: c0fdf799d624fd6016643fe18cb93166e09d9314e00d0a7d0970fbdaf26cd218
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are algorithmically generated and hosted on disposable domains, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://crysiq.ru/uplcv?utm_term=baixar+mapas+offline+google+maps+android PDF link annotation
    • http://ranahytta.com/ckfinder/userfiles/files/9797190987.pdfIn PDF document text
    • https://cvssteelex.com/ckfinder/userfiles/files/dixojemawawupodagogi.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/kugolulijenoxanopujafisuf.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/7191807834.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143932178b84---gupeg.pdfIn PDF document text
    • https://arendic.cl/files/62073658323.pdfIn PDF document text
    • http://nanumed.ro/uploads/files/10078650520.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/48793385671.pdfIn PDF document text
    • https://muachungbaohiem.com/uploads/userfiles/file/febelizoza.pdfIn PDF document text
    • https://curvy.tw/upload/files/palekegijanipomigowuto.pdfIn PDF document text
    • http://faptvmedia.com/userfiles/file/wetonimem.pdfIn PDF document text
    • http://xn--80aaa1acmiejxr6d7fg.xn--p1ai/data/files/28841131010.pdfIn PDF document text
    • https://living-stone.lu/userfiles/files/xarafuwowilobelij.pdfIn PDF document text
    • http://lavalnerina.it/userfiles/file/judizovoturuxeralafu.pdfIn PDF document text
    • http://373113.linker.tw/files/6947759119.pdfIn PDF document text
    • http://unionnutritech.com/upload/files/65371073960.pdfIn PDF document text
    • http://indianapit.thriftstorewebsites.net/flash/indianapit.thriftstorewebsites.net/file/dilix.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/viropirubaxaru.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/2455114730.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/48566325422.pdfIn PDF document text
    • http://munnartourism.com/uploads/file/xojoluxajatiwifiwomowubis.pdfIn PDF document text
    • https://nhomphuongnam.com/upload/files/kutumakezivobeloduzefuj.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/buzivado.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/35611406527.pdfIn PDF document text
    • http://technocom.pl/editor/file/64920415930.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/6708528783.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_off0000e268.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE268 16972 bytes
SHA-256: ab6740391ca031bef0d55e49d981a86eda2d09dfaf81132b1dcac06c780f05b8
font_01_sfnt_off00010e08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001261f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1261F 10896 bytes
SHA-256: 6202c21604d39de21ab145246a66573790f81239f83148ec8d1760e80b7ef0e2