Malicious PDF — malware analysis report

Static analysis result for SHA-256 afb16530f87d0dbc…

MALICIOUS

PDF

83.3 KB Created: 2021-06-12 05:24:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: cb2b2586570ba304c6bdf36c247e2b65 SHA-1: 5b58c24db6ee43e7bf7acb8eedcace6f1d356899 SHA-256: afb16530f87d0dbc7618b684604f3a91ac94d6f8a173c55294b61bbb5630491f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While 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 0.9998

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://catamma.ru/uplcv?utm_term=haar+transform+in+digital+image+processing PDF link annotation
    • http://growlink.biz/userfiles/file/nijazebirokok.pdfIn PDF document text
    • http://abpaluso.com/upload/file/2563208096.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/89581461612.pdfIn PDF document text
    • http://fuga-hotel.com/CKEdit/upload/files/koxedozewetu.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/9b2tc7e9bdcs3kmugvm04spvqs/59693969494.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/73038245821.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/f387c51334f38e1d7e803fe33d1839fd/92195957819.pdfIn PDF document text
    • https://seerupit.dk/assens/file/pikebalisuseba.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609bbe23799ae---getexigu.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5bf39ab31---90643264348.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/gupadomepoguruxitera.pdfIn PDF document text
    • http://falerisztika.hu/tmp/39338319666.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/2fcf2b8197e948d1e5a6eb7ae247f159/rapudelum.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/59e44b0cad690f92b113bc2acbaabdd4/telopi.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/r1he566g2kchbhq8dmgbuqhdae/vewotisa.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079fd0f797be---loxeboxe.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc50f396ccf---5541617309.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c3fdb456492---78376029432.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000107c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C7 5436 bytes
SHA-256: ff4a7c75961d3584e050b6d9464eab305f855275893888835be31db5f43d5f60
font_01_sfnt_off00011a31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A31 11204 bytes
SHA-256: a089db530edafc6719301679461d1938486048a58c245cc6da64b4df813ac733