Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f8df8d4b8a16d0a…

MALICIOUS

PDF

68.8 KB Created: 2021-09-27 21:43:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3bc7e073636bfe158c783aedb487d5e9 SHA-1: b318269b923d071df57f2e38f67ed4369289a680 SHA-256: 7f8df8d4b8a16d0aa4337e967bdebeabe31604fbcd9d44b66debd5eb30501227
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many hosted on disposable or compromised domains, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and heuristic firings point to a malicious PDF.

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 http://studiotecnicopetrillo.eu/userfiles/files/zunawe.pdf In PDF document text
    • https://gcs.kz/data/content/file/46623411348.pdfIn PDF document text
    • http://goodfortune.hk/UpLoadFile/file///petulerufugujilewar.pdfIn PDF document text
    • http://hockeydh.com/files/ups/files/90156376971.pdfIn PDF document text
    • http://phaptangpgvn.net/app/webroot/upload/files/zodizepenijafaxenixeg.pdfIn PDF document text
    • https://ons-station.com/editor_upload/file/jorefebevofadapabot.pdfIn PDF document text
    • https://gangwontaxi.com/FileData/ckfinder/files/20210917_216F140167A8C4F7.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16136864812ae5---rudorizis.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/xokibobubexewugazut.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/c7d5e7aa290c9caa63d9f44e42a12756/80255964203.pdfIn PDF document text
    • http://infiniti.e-library.tw/uploads/files/27038210451.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/70172913301.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/18046bb18883effe169324cf263fbfc8/58093593870.pdfIn PDF document text
    • http://innovatepc.com/userfiles/file/68882184160.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/33597516159.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/sidagusuzakewoxetebomog.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109042029382504.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/zezakosetovosiwefapu.pdfIn PDF document text
    • http://honeycontacts.com/uploades/userfiles/file/masorojetifiw.pdfIn PDF document text
    • http://enkepharma.com/upload/files/65157292963.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcca75c29c---47875703645.pdfIn PDF document text
    • https://fitness-base.tw/uploads/files/202109201948547474.pdfIn PDF document text
    • http://grotech.in/userfiles/file/64098293477.pdfIn PDF document text
    • http://montpellier-businessplan.fr/mbp/upload/images/images/upload/ckfinder/geforutubunow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=cool+words+with+nPDF 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_off0000b379.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB379 14336 bytes
SHA-256: eb0aaeb31ead8ddfd97ed3a46607aa3bc1fe5ac974c009d881e89d16efd52300
font_01_sfnt_off0000d70b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD70B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF22 10168 bytes
SHA-256: 1f155106dd8666eb7cfbe4271c0f69bc59d1f201b3ef5b7b4ca71a10ba053b38