Malicious PDF — malware analysis report

Static analysis result for SHA-256 337bfd4f3ba722b8…

MALICIOUS

PDF

73.7 KB Created: 2021-09-03 08:20:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a4e1ae29ae905dc69c1f92474e248c2a SHA-1: 8785842ecf339a811eed8ae583cd9d71c6087300 SHA-256: 337bfd4f3ba722b8383dda0ce4a1f5faf066fdadda34ca9a1dd60f22c561269c
154 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URIs and link farms points towards an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8092

Heuristics 5

  • 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
  • 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://pappteam.hu/userfiles/file/wafegifilalijavexudaloxi.pdf In PDF document text
    • https://chungcungoaigiao.net/uploads/files/tofadumabakezexupawaxa.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/580780c7a448c57ffc91a0c17fdaaf16/24542365066.pdfIn PDF document text
    • http://retroldn.com/userfiles/file/60543299405.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/92468481032.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/53400825009.pdfIn PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/59638423713.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202107051118.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/60458793425.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608215cb57a10---xopubimutuviwomi.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/93389435961.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adaed655ece---xejixaxutox.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/zururuxegikul.pdfIn PDF document text
    • https://unosms.us/userfiles/file/jegusame.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/88062050998.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/39454794909.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/r32valail09f31mem8uevpjcg5/rubikivekufe.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/34507123385.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a15bde7a9a0---29968164749.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609665bde4eaf---21076965693.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/56cd85e06f8dc765b3c9e7f20030e024/81974342413.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a676c9a31d6---devek.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160766632cd6e6---91989012005.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/vomipojobobetofuwaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=discussion+starters+speaking+fluency+activities+for+advanced+esl%2Fefl+students+pdfPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE675 11204 bytes
SHA-256: d6c1f761283ec31a5ccab20db360ce831c1e0e49c06ace5ad65cc45d9473675c
font_01_sfnt_off000100bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BB 18060 bytes
SHA-256: ec2e6e8b784dad8a01a750400a83768776f0782e220878ecab5d6a78f5933bf3