Malicious PDF — malware analysis report

Static analysis result for SHA-256 52ef49d48c1449ea…

MALICIOUS

PDF

82.7 KB Created: 2021-06-24 16:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: ac91ecc65cd70026f45c5382fb2bd35e SHA-1: bdab732a6c5a636d6f7b572c4fcc542ddd041e5b SHA-256: 52ef49d48c1449ea9d448c1a9de47f00f5d951eedde81429c82704267f604b44
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple distinct hosts, many of which are associated with compromised CMS uploads. The embedded URLs and the PDF structure suggest an attempt to lure users to external sites, likely for phishing or malware distribution.

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 https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/3o582b8fcvbmdhnopaknavplp9/tusap.pdf In PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/93793046207.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160876f91e83ec---96796321897.pdfIn PDF document text
    • http://rheinmotel.com/userfiles/file/rasekujazuworerop.pdfIn PDF document text
    • https://ladangmimpi.com/contents//files/25759925358.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/ec6jg0a087308fgi8ol2i0kh56/kigaxurowo.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/0805d20d106b5d9431133f24a2433b7f/60397161931.pdfIn PDF document text
    • https://avenue102.com/uploads/file/878348037.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/n8f20v5ksjq20mv5938ufh8mmk/25877467909.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/rimuzilogovok.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/20852977380.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607bab5a3703c---79622812442.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/tta1uc3ce7fdu750g1pdb1gfvn/4554014154.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/52de7a344722c22b9000a53fa2d57acc/17352891435.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a3ce2f343---61858770220.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210614042506164.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/zuwabarivamanazexojimum.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/8945e5353e9fe0f665c9c56aeca1147e/mojuzuzosutarumijegaz.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/PmAiG5ZyT-k/uplcv?utm_term=food+microbiology+lecture+notes+pdfPDF 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_off00010574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10574 5460 bytes
SHA-256: 67dd946129a46f9847a7ca0bb7d1e798d79bb785c0f013b6f58f43a16dbd8d9a
font_01_sfnt_off000117fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117FE 10960 bytes
SHA-256: 4b23c846ae887ae1067fc19fb13b7dbb8ae241f1e5779b425b55fdd3f103f945