Malicious PDF — malware analysis report

Static analysis result for SHA-256 16ab7b471ab36db5…

MALICIOUS

PDF

64.2 KB Created: 2021-06-24 20:44:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3c8ce9d4a74ea6bd31b9525d43469bed SHA-1: 2da8970a926221636b8fb5f83efc09a30a0760ee SHA-256: 16ab7b471ab36db54a891eb801fec2043bec7f1eda42ff9bbfa7cee211b0558d
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Multiple heuristics point to the PDF acting as a link farm, directing users to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs and the document's structure, despite the garbled body text, support the conclusion that it is designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://work4shop.cz/userfiles/file/mebezabizudej.pdf
    • http://cropscipublisher.com/files/upfiles/file/lamibamoxi.pdf
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/9865de08e452cda369e6fe8a4f56f425/25356593176.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160adb0c4f1ef3---gakalakomo.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/1702612e4cfd19a6da03921f7bac028d/dupanof.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3ca56edc3---misejodofalovopifuwixefu.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e077e4b755---vopuvez.pdf
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/h3841avgse6psj6l1jd7ku17t4/xowifezuverikipajaxu.pdf
    • http://neonatal-surgery.ru/userfiles/files/jofuweruvigatujone.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/124iq0nkpfvafh1lbt01m2qst3/nasimelamuzeba.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/kusojibigamolekod.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/g1mo6cbmbop24q5mf22tlgubs7/78402808944.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609754ba552b8---17008004590.pdf
    • http://konyaozgunmobilya.com/userfiles/file/20483633945.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/kbprrpc12rt325jnt2cato6r66/nolirupipunufiwuxijejo.pdf
    • https://actor-conseil.com/files/file/mikisizukadapi.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/cedcf31b77310d723149dd342748c14a/66562662335.pdf
    • http://kfnmsz.com/upfolder/e/files/20210623055616.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=gearbox+parts+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bf95.bin
621df8758ea63a0b53ea823addcf7c9dcf6394f8db287d6085c2ca7ef08b14bd
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF95 5244 bytes
font_01_sfnt_off0000d179.bin
be808dd6c6764a02129453768b88d5e33eb5ffcbd2bb47acf8cd8e87474dfb35
pdf-font-stream PDF embedded font (sfnt) at offset 0xD179 9700 bytes