Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa31edbbf0fcfc9f…

MALICIOUS

PDF

102.2 KB Created: 2021-10-04 17:01:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 2a06a4be6aa17154ebd722a768676354 SHA-1: efbe61918fdef684f4c9dd2e8c17bff9ef1a6c34 SHA-256: aa31edbbf0fcfc9fe7f0a3dcce88d739378704ade929f52f5bb59cc9c7c39b8d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm. Some links point to compromised WordPress sites, suggesting a potential distribution point for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9867

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://wsm.hk/images/files/45220680662.pdf In PDF document text
    • https://alperbehang.nl/userfiles/file/befivegawoto.pdfIn PDF document text
    • http://yokohama-model.com/userfiles/files/75436863131.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c321628ab9---5805885698.pdfIn PDF document text
    • http://azinsaghf.com/cache/fck_files/file/26809773600.pdfIn PDF document text
    • http://jonellchem.com/upload/files/63604796168.pdfIn PDF document text
    • http://elisa5888.com/shopadmin/upload/files/29777039785.pdfIn PDF document text
    • http://fd-health.com/upload/ckeditor/files/20126757040.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/96971614603.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/wufezifadosubovuwixi.pdfIn PDF document text
    • http://01host.ru/userfiles/files/44381033329.pdfIn PDF document text
    • http://kazuma.ru/ckfinder/userfiles/files/20144828656.pdfIn PDF document text
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210901171802.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/161336aeb59493---suvowutovemopo.pdfIn PDF document text
    • http://onlinetalk.jp/app/webroot/img/fckfiles/file/disajef.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/pavokubiluwejuxex.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/37625710754.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16155e1422d5b0---kirofusavapusubiduni.pdfIn PDF document text
    • https://stonebuild.bg/f/uploads/files/67373641550.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1631004935.pdfIn PDF document text
    • http://sevennews.com.br/ckfinder/userfiles/files/6226784591.pdfIn PDF document text
    • https://goldfieldssanddrags.com.au/ckfinder/userfiles/files/74765515245.pdfIn PDF document text
    • https://dolaodong.com/userfiles/file/71431016696.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/64blttq7l9ak8s2s54p8euhff2/govoxopigodisivopokomine.pdfIn PDF document text
    • https://anne-berger.de/sites/anne-berger.de/files/fkcfile/vinavunudidis.pdfIn PDF document text
    • https://cobaltinc.org/userfiles/file/97368490611.pdfIn PDF document text
    • https://hankilfood.com/upfile/files/tovekew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=call+me+by+your+name+screenplayPDF 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_off000126ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013ebe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EBE 20100 bytes
SHA-256: b8a7761a74abccabc9dae255bcbe2273031482b463ef98c5454790213ad89858
font_02_sfnt_off00017256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17256 10732 bytes
SHA-256: de384d21587619c9e3b0da7d5b6521923d82d3682c6d69305094072e6c8ad0cc