Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a1315e7a5e9d557…

MALICIOUS

PDF

71.0 KB Created: 2021-10-02 10:07:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0c36860c503b036576d9345140843426 SHA-1: cf54d0c7e5f8b77e1f11a4c2c44ec872331538a6 SHA-256: 7a1315e7a5e9d5570483df1cdb5dc46e77844d833e2366d6c76ffaa188af94db
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to compromised WordPress uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, but the presence of external URIs and link farm heuristics strongly indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://inwebjor.ru/uplcv?utm_term=pierce+the+veil+bulls+in+the+bronx+meaning PDF link annotation
    • https://sindhuinvestment.com/ckfinder/userfiles/files/99956113261.pdfIn PDF document text
    • http://offerseir.com/basefile/offerseircom/files/84969392402.pdfIn PDF document text
    • http://centrlita.ru/archive/image/file/47736460038.pdfIn PDF document text
    • http://esistore.com/userfiles/file/24866687232.pdfIn PDF document text
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/98785124705.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/bfo8v10ov50dd2hi78jc3mk0dv/tofadex.pdfIn PDF document text
    • http://ibrahimabuomira.com/ckeditor/ckfinder/userfiles/files/47245556869.pdfIn PDF document text
    • http://el-system.jp/uploads/2012/files/kifananuwuwobelu.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/20707383335.pdfIn PDF document text
    • https://035620126.tw/upload/greenkitchen/files/96123136019.pdfIn PDF document text
    • http://digilit.ir/basefile/digilitir/files/nejokabidapobudebedizo.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/19819908729.pdfIn PDF document text
    • https://2b3la571ga-70p.com/contents/files/zotawidezixovusat.pdfIn PDF document text
    • http://architettorobertafasola.eu/userfiles/files/wugomatibumito.pdfIn PDF document text
    • https://bakwanudang.com/contents/files/delevasizekomo.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/gobipikituligof.pdfIn PDF document text
    • https://sindonis.com/userfiles/file/96703477329.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/zamasapeja.pdfIn PDF document text
    • https://kalendarz.probik.pl/fckeditor/userfiles/file/78066395366.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/75cd15181d0a8df2697080105dfe7aa5/dukijawinagafisazakaraku.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/161527796e4eab---44263039604.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/35079150429.pdfIn PDF document text
    • https://lighthousemacau.com/html_upload/file/64715664336.pdfIn PDF document text
    • https://ayurmitra.com/files/file/lixuwuvudopole.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_off0000b289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB289 16392 bytes
SHA-256: acb238daf14040492f85506fb8b4f8b29e643b99366302613016686066fd2421
font_01_sfnt_off0000dc03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f41a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF41A 11088 bytes
SHA-256: 4e245a5de72b5d2e60be66de92373bbae74593ee5a7cc22b594be2d17e980d75