Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f9a37c81473934f…

MALICIOUS

PDF

69.0 KB Created: 2021-09-17 22:50:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a52baaf47154e578b381ee1195d4b528 SHA-1: 0579608bc4f2eb35eb00357d4147451d5fb9bd52 SHA-256: 8f9a37c81473934fc82220553a2b8547d9b99fe61b52b2fc891150424a4c7912
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF is identified as an image-only lure, typical for phishing or malware distribution, containing numerous links to external sites hosted on potentially compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious content or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://ciiinnovationsummit.com/ci/userfiles/files/35240870908.pdf In PDF document text
    • http://zuszdounky.cz/files/rogusowojabukim.pdfIn PDF document text
    • https://plantbiochem.com/ckfinder/userfiles/files/luzozeso.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/77072026211.pdfIn PDF document text
    • http://kiddeefire.com/media/userfiles/files/33445932269.pdfIn PDF document text
    • http://receptlap.hu/files/20904954041.pdfIn PDF document text
    • http://35ju.21tg.cn/uploadfile/ckeditor/files/23228636540.pdfIn PDF document text
    • https://mygoaltv.com/ipp/images/uploads/files/joponukikasizuvasigev.pdfIn PDF document text
    • https://altaitur.com/ckfinder/userfiles/files/67602742649.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/86f1a7a414e0c6be1708b0814bd5ceb2/48868088134.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/161402e299ece1---97863244912.pdfIn PDF document text
    • http://norilskgu.ru/userfiles/file/98821974713.pdfIn PDF document text
    • http://seto.cz/uploads/padapafip.pdfIn PDF document text
    • https://adproissy.emailingmanager.com/uploads/editor/file/35079099478.pdfIn PDF document text
    • https://indolabtek.com/Uploads/userfiles/files/7143614214.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/16764426918.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161360536a9883---98001556480.pdfIn PDF document text
    • http://chengzechem.com/upload/files/gefegemipetema.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/21632368653.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/gelemofuwifimepiku.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/29174578192.pdfIn PDF document text
    • http://www.motionmantra.com/userfiles/files/71120484090.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/motexa.pdfIn PDF document text
    • https://nucamsa.es/userfiles/files/37180182479.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/24556485661.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=best+rom+downloader+for+androidPDF 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://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_off0000b29d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB29D 10656 bytes
SHA-256: f4039d4fbc8b2f155dd21c10eed2abce737b530f5fcfba3b6368f736858158fb
font_01_sfnt_off0000cb13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB13 14060 bytes
SHA-256: 5547034500ffa40aee0ec7ea40d6df18d2c986b0877a68ae24156580bfcf44c7
font_02_sfnt_off0000ee11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1