Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3d8c1eea9074947…

MALICIOUS

PDF

83.6 KB Created: 2021-09-16 06:29:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 06b9de3a1ec9b2a8d8f2d1da65cbbbe6 SHA-1: 1eb174a947ec66884f6f842fcbc5c3fa6de989ea SHA-256: a3d8c1eea907494770a54787793bef9eb2026acf875beb9c3dbdaf3787a2e492
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's part of a link farm designed to host numerous other PDF files, likely for phishing or malware distribution. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics point towards a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • 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://ttmm.co.jp/ckfinder/userfiles/files/93402549533.pdf In PDF document text
    • http://trieuduong.com/images/Download/zimibujevifomobo.pdfIn PDF document text
    • http://hizirferforje.com/admin/fckeditor/editor/images/file/kavekukisiwodolewaj.pdfIn PDF document text
    • http://villkasz.hu/editor_up/sajemowiforugunuwokogumor.pdfIn PDF document text
    • https://www.chablis-gautherin.com/ckfinder/userfiles/files/bozafekexemelogu.pdfIn PDF document text
    • https://vjlabor.pitscovn.com/uploads/Upload/files/35988612477.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/63381284736.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e74b80ad4---28291039953.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/55289188986.pdfIn PDF document text
    • https://matricula.arendic.cl/files/29284288897.pdfIn PDF document text
    • http://adasbruiloften.nl/userfiles/file/bovelo.pdfIn PDF document text
    • http://rc-modeller.se/images/file///61236737096.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/h5g670q6rng9n2j10vv6b4v9oo/deleruxugaka.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gufezefavopipapajigat.pdfIn PDF document text
    • https://mlbcsimleague.com/ckfinder/userfiles/files/80188685741.pdfIn PDF document text
    • https://nezrenpin.com/calisma2/files/uploads/87370070118.pdfIn PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/29786445846.pdfIn PDF document text
    • https://lecachet.fr/docs/files/kovejag.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/fipawopefuworimifibojora.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/gugigejebanogiw.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/newasami.pdfIn PDF document text
    • http://luyenthidhcanhsat.com/Images_upload/files/rifevevamigog.pdfIn PDF document text
    • https://ever.dacola.com/upload/files/legobudikalijezi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=get+contact+mod+apkPDF 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_off0000e260.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE260 18072 bytes
SHA-256: 9242b2e6573ac236cf52feab45ee444b8f0c97b4dab7953e14254705414b3936
font_01_sfnt_off0001114a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1114A 10400 bytes
SHA-256: 07a42abb3a83028465fe20a75699806c1fdfdcf5d1634549e3c9802152fc8fb4
font_02_sfnt_off000128da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1