Malicious PDF — malware analysis report

Static analysis result for SHA-256 33dad93a21fa8845…

MALICIOUS

PDF

88.2 KB Created: 2021-09-09 22:32:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5646f4d38a5c82b7f62f12fb97f118a6 SHA-1: 1c0304d02825591dbe9911b0db2c95b9b323268b SHA-256: 33dad93a21fa88456a90bedd17e9d15724b260902b3c70235a34faab6c7a7e56
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to potentially harmful sites. The presence of these link farms and the overall detection as a phishing trojan strongly suggest a malicious intent to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://chcial.ru/uplcv?utm_term=how+do+i+turn+off+amber+alerts+on+android PDF link annotation
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/e9ed5699ecbd612646c44195707c5e42/kojepovekikidef.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/27600431451.pdfIn PDF document text
    • http://thienlongadv.com/upload/files/nupaxibitolojugidilidufa.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1612f9be4ea6b9---25394231473.pdfIn PDF document text
    • https://habrit.tw/ckfinder/userfiles/files/wakimubu.pdfIn PDF document text
    • https://dreptultau.hotnews.md/upload/userfiles/files/pawovozolitades.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/75961611495.pdfIn PDF document text
    • http://dongphat.net/upload/files/21738019945.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/sebamare.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/widom.pdfIn PDF document text
    • https://dom4m.lv/userfiles/files/kuduguronomuxodaparaviso.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/92448463820.pdfIn PDF document text
    • https://bruceleevideos.org/images/file/82725061170.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/ruwarifakegixogubawoj.pdfIn PDF document text
    • https://artgreen.vn/attachment/files/loluxumogise.pdfIn PDF document text
    • http://ajmason.com/admin/ckfinder/userfiles/files/xopodefitesofela.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/nixufamonotikekafadegojoj.pdfIn PDF document text
    • http://2m-m.eu/userfiles/files/wezitowejupozureponuz.pdfIn PDF document text
    • https://aodaixuan.vn/app/webroot/upload/image/files/93938687347.pdfIn PDF document text
    • http://gewald.ru/content/Files/mewag.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135e895b0c3c---fifojasavezi.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/zumewitofajakurarolid.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/un84ha2l6shciba8ih2f41l9td/11499484679.pdfIn PDF document text
    • https://dzido.pl/userfiles/file/zelelafapujupinu.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/pajexet.pdfIn PDF document text
    • 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_off0000ef1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001072e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072E 19520 bytes
SHA-256: d9234e668358b5dbf27bad274e86d11cbcceb7cce35d164f8b5e48d5d5937de8
font_02_sfnt_off000139b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139B6 10832 bytes
SHA-256: 4d41470d32a51de26349477b8357502f01f511c0b17caa5fa31302b0d1001f71