Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef76774e06dccffa…

MALICIOUS

PDF

79.2 KB Created: 2021-09-09 10:26:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 515dba5535e2b0e1f34a8e363614e3ad SHA-1: f5cdc74abf0c3c80c38924c880289ef008208752 SHA-256: ef76774e06dccffa018b3a226cf06e10c93e3db30fee44e5ef14692436644b36
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. While no scripts were explicitly extracted, the PDF format often utilizes JavaScript for malicious redirection, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://duproject.com/uploadEditor/files/63635203110.pdf In PDF document text
    • http://statsale.com/data/upload/ck/files/60412908674.pdfIn PDF document text
    • http://nhadep30giay.com/uploads/image/files/40337689145.pdfIn PDF document text
    • http://dulwichtaxi.com/survey/userfiles/files/faxakawes.pdfIn PDF document text
    • https://newshieldinsurance.com/demo/gsa/final/images/file/legobarabawitewemasatev.pdfIn PDF document text
    • https://ap-qatar.com/userfiles/files/34119210414.pdfIn PDF document text
    • http://tantex.org/tantex/tantexuserfiles/file/votizodevajifipi.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/40409786369.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/45618470627.pdfIn PDF document text
    • https://eastmanllc.net/ckfinder/userfiles/files/wolevo.pdfIn PDF document text
    • http://studiomalpocher.it/userfiles/files/xumovutewafejojarenopimot.pdfIn PDF document text
    • http://dinobajka.pl/Upload/file/44545332957.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/dujomosomukemalidepunaki.pdfIn PDF document text
    • https://tjpapigroup3.com/contents/files/39768412156.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/cb27e38066a4a9578b23644deef3a2cb/deduvuvube.pdfIn PDF document text
    • http://hzzxtl.com/UploadFile/file/20210908234928441.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/vezovokin.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/12488594769.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/s75a0u5bpjeekva2o6b2o39qei/79911136566.pdfIn PDF document text
    • http://yeditepegumruk.com/userfiles/31972284768.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/vatepomemagelu.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/cfe9b8ecb72eb0977325229945a37ad4/1731814176.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=not+so+happy+wheelsPDF 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_off0000d1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F1 17768 bytes
SHA-256: 32d53e5d40912989c0042269f4ac343811fa428c716f478f479f4570cf3a8595
font_01_sfnt_off00010048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10048 10228 bytes
SHA-256: 4f42da3272a49856f06d074e3ccb64fa5d625387d842b21ab1d0d82db723aab6
font_02_sfnt_off0001178e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1178E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1