Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f3b39a9da04375d…

MALICIOUS

PDF

112.2 KB Created: 2021-06-19 14:37:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 0868b2cfba5d8b52ef18ff94b50a095a SHA-1: b6ed897176cf0d9a0332f2089702393b75e942ef SHA-256: 4f3b39a9da04375dc647b43eca2dc49bad824be0cef964042008faf5ac87e28f
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, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm on disposable hosting. The document body, though heavily obfuscated, suggests a lure related to 'how to do apa with no author', likely a pretext to drive users to these malicious links.

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 http://musiconthebay.org/clients/2/26/269dd5bc96e197da989a8dccc71442af/File/27272977327.pdf In PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607346293309b---20180700921.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/d60cea5bcdd99fda158b663d8a568de1/67338145805.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085eb0d0a154---xiwifazuliwitapo.pdfIn PDF document text
    • http://allasclub.com/campannas/file/56839453824.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/f332255874670f0f17790824e2944f33/51843756398.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pq81mk8fkr7rue8cvr4jrfcf12/jokerer.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/ead0dcf0143eb391b4eb8413694aa65c/movigijax.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/tevidofokami.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b72f240a6fb---36351915503.pdfIn PDF document text
    • https://ewastexperts.com/userfiles/files/43511684730.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16083dbaa22f64---90764746427.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/3980788063.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202106190259.pdfIn PDF document text
    • http://asbazainville.org/userfiles/file/gixeduzepafezufese.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/a39e1af5526d2a163737cb41eed42f22/28260836188.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+do+apa+with+no+authorPDF link annotation
    • 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_off00017b9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17B9A 4892 bytes
SHA-256: 13189a29f8b4d7705b787a35ce9c5c26d20d826e5e78529c0291fe43bfff4b1c
font_01_sfnt_off00018c43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18C43 11624 bytes
SHA-256: e4cb99f9ddfb32544bf28c605ff87b7dcd03d86a2860ffc4d83ae0ec52b886c2