Malicious PDF — malware analysis report

Static analysis result for SHA-256 856d6d51b06c7188…

MALICIOUS

PDF

77.4 KB Created: 2021-09-15 13:35:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 857dac5c1f8aeaf5300a5eab18c90460 SHA-1: cdefe5c1779e1285e87e5008f5a494b8b4bfa2dc SHA-256: 856d6d51b06c718808d8d8e0650ce2d7ec8163d2afc2b1b1145a5e4a8c61e9ed
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate it functions as a link farm with a deceptive download button, aiming to trick users into downloading further malicious content. The ML classifier strongly supports the malicious verdict, and numerous unknown URLs suggest a broad distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://tlproduct.com/userfiles/file/jokonigojogupikupituxelox.pdf In PDF document text
    • http://ryouhurt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/werovajonagewugu.pdfIn PDF document text
    • http://gulfcoastlist.com/userfiles/file/wojijew.pdfIn PDF document text
    • https://kawanmto.com/contents/files/60606342647.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/4989712223.pdfIn PDF document text
    • http://bfcy88.com/uploads/files/zibewemovagavelijep.pdfIn PDF document text
    • http://spamsmsgiare.com/media/ftp/file/79072772875.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/43787293385.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/33516860008.pdfIn PDF document text
    • https://silky.ae/images/bulk_images/files/gabuwete.pdfIn PDF document text
    • https://florerialafloresta.com/ckfinder/userfiles/files/11567363846.pdfIn PDF document text
    • http://nghieuphong.com/upload/files/gibimixosanumif.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/pakoduronokisapelilar.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/27d8c27f9c95b6248f8ca4adf90c4e5c/42739686853.pdfIn PDF document text
    • http://thecargonepal.com/userfiles/file/lazikuxupetot.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/tusamumupor.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/39278228315.pdfIn PDF document text
    • http://orthodoxvaidikasanghom.org/userfiles/file/niloditawavoduluge.pdfIn PDF document text
    • https://dmshospital.com/mm_engg/files/bibos.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/6139524707.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/80932450299.pdfIn PDF document text
    • https://moveo-sport.pl/userfiles/file/wezalitedito.pdfIn PDF document text
    • http://omnoiptv.com/outscapes/admin/ckeditor/uploads/ck/files/xopoxi.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/48705819057.pdfIn PDF document text
    • http://koala-al.com/d/files/20265113043.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/30541662761.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a867e05003---945111950.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/folosidumajuteved.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=watch+the+fabulous+lives+of+bollywood+wives+online+free+englishPDF 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_off0000c4fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD13 11256 bytes
SHA-256: def4fa037871be4d560ca2b64f6815dd7517bef3b703439557af8cc3d4ac3d02
font_02_sfnt_off0000f744.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF744 19120 bytes
SHA-256: 2038ab4253e1619b51107859a237a3a41c3be7725b345177ccffb57a8efccb15